[CORE:INTERRUPT_VECTOR:MEMORY:PACKAGE:POWER:PROGVOLT:LOCKBIT:PROGRAMMING:FUSE:ADMIN:IO_MODULE:ICE_SETTINGS] V2E AVRSimCoreV2.SimCoreV2 [] [] [] 32 $00 $1B $1A $1D $1C $1F $1E 23 $000 RESET External Pin,Power-on Reset,Brown-out Reset,Watchdog Reset,and JTAG AVR Reset. See Datasheet. $002 INT0 External Interrupt Request 0 $004 PCINT0 Pin Change Interrupt Request 0 $006 PCINT1 Pin Change Interrupt Request 1 $008 TIMER2 COMP Timer/Counter2 Compare Match $00A TIMER2 OVF Timer/Counter2 Overflow $00C TIMER1 CAPT Timer/Counter1 Capture Event $00E TIMER1 COMPA Timer/Counter1 Compare Match A $010 TIMER1 COMPB Timer/Counter Compare Match B $012 TIMER1 OVF Timer/Counter1 Overflow $014 TIMER0 COMP Timer/Counter0 Compare Match $016 TIMER0 OVF Timer/Counter0 Overflow $018 SPI, STC SPI Serial Transfer Complete $01A USART0, RX USART, RX USART0, Rx Complete $01C USART0, UDRE USART, UDRE USART0 Data register Empty $01E USART0, TX USART, TX USART0, Tx Complete $020 USI START USI Start Condition $022 USI OVERFLOW USI Overflow $024 ANALOG COMP Analog Comparator $026 ADC ADC Conversion Complete $028 EE_READY EEPROM Ready $02A SPM_READY Store Program Memory Read $02C LCD LCD Start of Frame AVRSimMemory8bit.SimMemory8bit 32768 1024 2048 $100 0 NA $00 $3F $60 $FF $20 $FF NA $FF NA $FE 0x01 NA $FD 0x010x020x040x080x100x200x400x80 NA $FC 0x010x020x040x080x100x200x400x80 NA $FB 0x010x020x040x080x100x200x400x80 NA $FA NA $F9 0x01 NA $F8 0x010x020x040x080x100x200x400x80 NA $F7 0x010x020x040x080x100x200x400x80 NA $F6 0x010x020x040x080x100x200x400x80 NA $F5 NA $F4 0x01 NA $F3 0x010x020x040x080x100x200x400x80 NA $F2 0x010x020x040x080x100x200x400x80 NA $F1 0x010x020x040x080x100x200x400x80 NA $F0 NA $EF 0x01 NA $EE 0x010x020x040x080x100x200x400x80 NA $ED 0x010x020x040x080x100x200x400x80 NA $EC 0x010x020x040x080x100x200x400x80 NA $E7 0x010x020x040x080x100x200x400x80 NA $E6 0x010x020x040x100x200x40 NA $E5 0x010x020x040x080x100x200x400x80 NA $E4 0x010x020x040x080x100x400x80 NA $DD NA $DC NA $DB NA $DA NA $D9 NA $D8 NA $C6 0x010x020x040x080x100x200x400x80 NA $C5 0x010x020x040x08 NA $C4 0x010x020x040x080x100x200x400x80 NA $C2 0x010x020x040x080x100x200x40 NA $C1 0x010x020x040x080x100x200x400x80 NA $C0 0x010x020x040x080x100x200x400x80 NA $BA 0x010x020x040x080x100x200x400x80 NA $B9 0x010x020x040x080x100x200x400x80 NA $B8 0x010x020x040x080x100x200x400x80 NA $B6 0x010x020x040x080x10 NA $B3 0x010x020x040x080x100x200x400x80 NA $B2 0x010x020x040x080x100x200x400x80 NA $B0 0x010x020x040x080x100x200x400x80 NA $8B 0x010x020x040x080x100x200x400x80 NA $8A 0x010x020x040x080x100x200x400x80 NA $89 0x010x020x040x080x100x200x400x80 NA $88 0x010x020x040x080x100x200x400x80 NA $87 0x010x020x040x080x100x200x400x80 NA $86 0x010x020x040x080x100x200x400x80 NA $85 0x010x020x040x080x100x200x400x80 NA $84 0x010x020x040x080x100x200x400x80 NA $82 0x400x80 NA $81 0x010x020x040x080x100x400x80 NA $80 0x010x020x100x200x400x80 NA $7F 0x010x02 NA $7E 0x010x020x040x080x100x200x400x80 NA $7C 0x010x020x040x080x100x200x400x80 NA $7B 0x400x010x020x04 NA $7A 0x010x020x040x080x100x200x400x80 NA $79 0x010x020x040x080x100x200x400x80 NA $78 0x010x020x040x080x100x200x400x80 NA $70 0x010x02 NA $6F 0x010x020x040x20 NA $6E 0x010x02 NA $6C 0x010x020x040x080x100x200x400x80 NA $6B 0x010x020x040x080x100x200x400x80 NA $69 0x010x02 NA $66 0x010x020x040x080x100x200x400x80 NA $64 0x010x020x040x080x10 NA $61 0x010x020x040x080x80 NA $60 0x010x020x040x080x10 $3F $5F 0x010x020x040x080x100x200x400x80 $3E $5E 0x010x020x040x080x100x200x400x80 $3D $5D 0x010x020x040x080x100x200x400x80 $37 $57 0x010x020x040x080x100x400x80 $35 $55 0x800x010x020x100x200x40 $34 $54 0x100x010x020x040x08 $33 $53 0x010x020x040x08 $31 $51 0x010x020x040x080x100x200x400x80 $30 $50 0x010x020x040x080x100x200x400x80 $2E $4E 0x010x020x040x080x100x200x400x80 $2D $4D 0x010x400x80 $2C $4C 0x010x020x040x080x100x200x400x80 $2B $4B 0x010x020x040x080x100x200x400x80 $2A $4A 0x010x020x040x080x100x200x400x80 $27 $47 0x010x020x040x080x100x200x400x80 $26 $46 0x010x020x040x080x100x200x400x80 $24 $44 0x010x020x040x080x100x200x400x80 $23 $43 0x010x800x02 $22 $42 0x010x02 $21 $41 0x010x020x040x080x100x200x400x80 $20 $40 0x010x020x040x080x100x200x400x80 $1F $3F 0x010x020x040x08 $1E $3E 0x010x020x040x080x100x200x400x80 $1D $3D 0x010x100x200x400x80 $1C $3C 0x010x100x200x400x80 $17 $37 0x010x02 $16 $36 0x010x020x040x20 $15 $35 0x010x02 $14 $34 0x010x020x040x080x10 $13 $33 0x010x020x040x080x10 $12 $32 0x010x020x040x080x100x20 $11 $31 0x010x020x040x080x100x200x400x80 $10 $30 0x010x020x040x080x100x200x400x80 $0F $2F 0x010x020x040x080x100x200x400x80 $0E $2E 0x010x020x040x080x100x200x400x80 $0D $2D 0x010x020x040x080x100x200x400x80 $0C $2C 0x010x020x040x080x100x200x400x80 $0B $2B 0x010x020x040x080x100x200x400x80 $0A $2A 0x010x020x040x080x100x200x400x80 $09 $29 0x010x020x040x080x100x200x400x80 $08 $28 0x010x020x040x080x100x200x400x80 $07 $27 0x010x020x040x080x100x200x400x80 $06 $26 0x010x020x040x080x100x200x400x80 $05 $25 0x010x020x040x080x100x200x400x80 $04 $24 0x010x020x040x080x100x200x400x80 $03 $23 0x010x020x040x080x100x200x400x80 $02 $22 0x010x020x040x080x100x200x400x80 $01 $21 0x010x020x040x080x100x200x400x80 $00 $20 0x010x020x040x080x100x200x400x80 $3800 $3FFF $0000 $37FF 64 256 4 $0000 $3F00 $3F00 512 8 $0000 $3E00 $3E00 1024 16 $0000 $3C00 $3C00 2048 32 $0000 $3800 $3800 [TQFP] 64 [LCDCAP] [RXD:PCINT0] PE0 [TXD:PCINT1] PE1 [XCK:AIN0:PCINT2] PE2 [AIN1:PCINT3] PE3 [USCK:SCL:PCINT4] PE4 [DI:SDA:PCINT5] PE5 [DO:PCINT6] PE6 [PCINT7] PE7 ['SS:PCINT8] PB0 [SCK:PCINT9] PB1 [MOSI:PCINT10] PB2 [MISO:PCINT11] PB3 [OC0:PCINT12] PB4 [OC1A:PCINT13] PB5 [OC1B:PCINT14] PB6 [OC2:PCINT15] PB7 [T1:SEG24] PG3 [T0:SEG23] PG4 ['RESET] PG5 [VCC] [GND] [TOSC2] XTAL2 [TOSC1] XTAL1 [ICP/SEG22] PD0 [INT0/SEG21] PD1 [SEG20] PD2 [SEG19] PD3 [SEG18] PD4 [SEG17] PD5 [SEG16] PD6 [SEG15] PD7 [SEG14] PG0 [SEG13] PG1 [SEG12] PC0 [SEG11] PC1 [SEG10] PC2 [SEG9] PC3 [SEG8] PC4 [SEG7] PC5 [SEG6] PC6 [SEG5] PC7 [SEG4] PG2 [SEG3] PA7 [SEG2] PA6 [SEG1] PA5 [SEG0] PA4 [COM3] PA3 [COM2] PA2 [COM1] PA1 [COM0] PA0 [VCC] [GND] [ADC7:TDI] PF7 [ADC6:TD0] PF6 [ADC5:TMS] PF5 [ADC4:TCK] PF4 [ADC3] PF3 [ADC2] PF2 [ADC1] PF1 [ADC0] PF0 [AREF9 [GND] [AVCC] 4MHz 25C TBD mA TBD mA TBD uA 4.0 5.5 4.0 5.5 [LB1 = 1 : LB2 = 1] No memory lock features enabled. [LB1 = 0 : LB2 = 1] Further programming of Flash and EEPROM is enabled. [LB1 = 0 : LB2 = 0] Same as previous, but verify is also disabled 6 11 0x03 0x03 Mode 1: No memory lock features enabled 0x03 0x02 Mode 2: Further programming disabled 0x03 0x00 Mode 3: Further programming and verification disabled 0x0C 0x0C Application Protection Mode 1: No lock on SPM and LPM in Application Section 0x0C 0x08 Application Protection Mode 2: SPM prohibited in Application Section 0x0C 0x00 Application Protection Mode 3: LPM and SPM prohibited in Application Section 0x0C 0x04 Application Protection Mode 4: LPM prohibited in Application Section 0x30 0x30 Boot Loader Protection Mode 1: No lock on SPM and LPM in Boot Loader Section 0x30 0x20 Boot Loader Protection Mode 2: SPM prohibited in Boot Loader Section 0x30 0x00 Boot Loader Protection Mode 3: LPM and SPM prohibited in Boot Loader Section 0x30 0x10 Boot Loader Protection Mode 4: LPM prohibited in Boot Loader Section LB1 Lock bit LB2 Lock bit BLB01 Boot Lock bit BLB02 Boot Lock bit BLB11 Boot lock bit BLB12 Boot lock bit 0xff,0xdf 0xff,0xdf 1,0x40,0x40,WARNING! These fuse settings will disable the JTAG interface! 1,0x20,0x20,WARNING! These fuse settings will disable the ISP interface! 2,0x01,0x00,WARNING! Disabling external reset will make the ISP interface inaccessible! 1,0x40,0x40,WARNING! These fuse settings will disable the JTAG interface! 1,0x20,0x20,WARNING! These fuse settings will disable the ISP interface! 2,0x01,0x00,WARNING! Disabling external reset will make the ISP interface inaccessible! 1,0x40,0x40,WARNING! These fuse settings will disable the JTAG interface! 1,0x20,0x20,WARNING! These fuse settings will disable the ISP interface! 2,0x01,0x00,WARNING! Disabling external reset will make the ISP interface inaccessible! 0x00,8.0 MHz 128 4 [LOW:HIGH:EXTENDED] 8 CLKDIV8 Divide clock by 8 0 CKOUT Oscillator options 1 SUT1 Select start-up time 0 SUT0 Select start-up time 0 CKSEL3 Select Clock Source 0 CKSEL2 Select Clock Source 0 CKSEL1 Select Clock Source 0 CKSEL0 Select Clock Source 1 46 0x80 0x00 Divide clock by 8 internally; [CKDIV8=0] 0x40 0x00 Clock output on PORTE7; [CKOUT=0] 0x3F 0x00 Ext. Clock; Start-up time: 6 CK + 0 ms; [CKSEL=0000 SUT=00] 0x3F 0x10 Ext. Clock; Start-up time: 6 CK + 4.1 ms; [CKSEL=0000 SUT=01] 0x3F 0x20 Ext. Clock; Start-up time: 6 CK + 65 ms; [CKSEL=0000 SUT=10] 0x3F 0x02 Int. RC Osc.; Start-up time: 6 CK + 0 ms; [CKSEL=0010 SUT=00] 0x3F 0x12 Int. RC Osc.; Start-up time: 6 CK + 4.1 ms; [CKSEL=0010 SUT=01] 0x3F 0x22 Int. RC Osc.; Start-up time: 6 CK + 65 ms; [CKSEL=0010 SUT=10] 0x3F 0x07 Ext. Low-Freq. Crystal; Start-up time: 32K CK + 0 ms; [CKSEL=0111 SUT=00] 0x3F 0x17 Ext. Low-Freq. Crystal; Start-up time: 32K CK + 4.1 ms; [CKSEL=0111 SUT=01] 0x3F 0x27 Ext. Low-Freq. Crystal; Start-up time: 32K CK + 65 ms; [CKSEL=0111 SUT=10] 0x3F 0x06 Ext. Low-Freq. Crystal; Start-up time: 1K CK + 0 ms; [CKSEL=0110 SUT=00] 0x3F 0x16 Ext. Low-Freq. Crystal; Start-up time: 1K CK + 4.1 ms; [CKSEL=0110 SUT=01] 0x3F 0x26 Ext. Low-Freq. Crystal; Start-up time: 1K CK + 65 ms; [CKSEL=0110 SUT=10] 0x3F 0x08 Ext. Crystal Osc.; Frequency 0.4-0.9 MHz; Start-up time: 258 CK + 4.1 ms; [CKSEL=1000 SUT=00] 0x3F 0x18 Ext. Crystal Osc.; Frequency 0.4-0.9 MHz; Start-up time: 258 CK + 65 ms; [CKSEL=1000 SUT=01] 0x3F 0x28 Ext. Crystal Osc.; Frequency 0.4-0.9 MHz; Start-up time: 1K CK + 0 ms; [CKSEL=1000 SUT=10] 0x3F 0x38 Ext. Crystal Osc.; Frequency 0.4-0.9 MHz; Start-up time: 1K CK + 4.1 ms; [CKSEL=1000 SUT=11] 0x3F 0x09 Ext. Crystal Osc.; Frequency 0.4-0.9 MHz; Start-up time: 1K CK + 65 ms; [CKSEL=1001 SUT=00] 0x3F 0x19 Ext. Crystal Osc.; Frequency 0.4-0.9 MHz; Start-up time: 16K CK + 0 ms; [CKSEL=1001 SUT=01] 0x3F 0x29 Ext. Crystal Osc.; Frequency 0.4-0.9 MHz; Start-up time: 16K CK + 4.1 ms; [CKSEL=1001 SUT=10] 0x3F 0x39 Ext. Crystal Osc.; Frequency 0.4-0.9 MHz; Start-up time: 16K CK + 65 ms; [CKSEL=1001 SUT=11] 0x3F 0x0A Ext. Crystal Osc.; Frequency 0.9-3.0 MHz; Start-up time: 258 CK + 4.1 ms; [CKSEL=1010 SUT=00] 0x3F 0x1A Ext. Crystal Osc.; Frequency 0.9-3.0 MHz; Start-up time: 258 CK + 65 ms; [CKSEL=1010 SUT=01] 0x3F 0x2A Ext. Crystal Osc.; Frequency 0.9-3.0 MHz; Start-up time: 1K CK + 0 ms; [CKSEL=1010 SUT=10] 0x3F 0x3A Ext. Crystal Osc.; Frequency 0.9-3.0 MHz; Start-up time: 1K CK + 4.1 ms; [CKSEL=1010 SUT=11] 0x3F 0x0B Ext. Crystal Osc.; Frequency 0.9-3.0 MHz; Start-up time: 1K CK + 65 ms; [CKSEL=1011 SUT=00] 0x3F 0x1B Ext. Crystal Osc.; Frequency 0.9-3.0 MHz; Start-up time: 16K CK + 0 ms; [CKSEL=1011 SUT=01] 0x3F 0x2B Ext. Crystal Osc.; Frequency 0.9-3.0 MHz; Start-up time: 16K CK + 4.1 ms; [CKSEL=1011 SUT=10] 0x3F 0x3B Ext. Crystal Osc.; Frequency 0.9-3.0 MHz; Start-up time: 16K CK + 65 ms; [CKSEL=1011 SUT=11] 0x3F 0x0C Ext. Crystal Osc.; Frequency 3.0-8.0 MHz; Start-up time: 258 CK + 4.1 ms; [CKSEL=1100 SUT=00] 0x3F 0x1C Ext. Crystal Osc.; Frequency 3.0-8.0 MHz; Start-up time: 258 CK + 65 ms; [CKSEL=1100 SUT=01] 0x3F 0x2C Ext. Crystal Osc.; Frequency 3.0-8.0 MHz; Start-up time: 1K CK + 0 ms; [CKSEL=1100 SUT=10] 0x3F 0x3C Ext. Crystal Osc.; Frequency 3.0-8.0 MHz; Start-up time: 1K CK + 4.1 ms; [CKSEL=1100 SUT=11] 0x3F 0x0D Ext. Crystal Osc.; Frequency 3.0-8.0 MHz; Start-up time: 1K CK + 65 ms; [CKSEL=1101 SUT=00] 0x3F 0x1D Ext. Crystal Osc.; Frequency 3.0-8.0 MHz; Start-up time: 16K CK + 0 ms; [CKSEL=1101 SUT=01] 0x3F 0x2D Ext. Crystal Osc.; Frequency 3.0-8.0 MHz; Start-up time: 16K CK + 4.1 ms; [CKSEL=1101 SUT=10] 0x3F 0x3D Ext. Crystal Osc.; Frequency 3.0-8.0 MHz; Start-up time: 16K CK + 65 ms; [CKSEL=1101 SUT=11] 0x3F 0x0E Ext. Crystal Osc.; Frequency 8.0- MHz; Start-up time: 258 CK + 4.1 ms; [CKSEL=1110 SUT=00] 0x3F 0x1E Ext. Crystal Osc.; Frequency 8.0- MHz; Start-up time: 258 CK + 65 ms; [CKSEL=1110 SUT=01] 0x3F 0x2E Ext. Crystal Osc.; Frequency 8.0- MHz; Start-up time: 1K CK + 0 ms; [CKSEL=1110 SUT=10] 0x3F 0x3E Ext. Crystal Osc.; Frequency 8.0- MHz; Start-up time: 1K CK + 4.1 ms; [CKSEL=1110 SUT=11] 0x3F 0x0F Ext. Crystal Osc.; Frequency 8.0- MHz; Start-up time: 1K CK + 65 ms; [CKSEL=1111 SUT=00] 0x3F 0x1F Ext. Crystal Osc.; Frequency 8.0- MHz; Start-up time: 16K CK + 0 ms; [CKSEL=1111 SUT=01] 0x3F 0x2F Ext. Crystal Osc.; Frequency 8.0- MHz; Start-up time: 16K CK + 4.1 ms; [CKSEL=1111 SUT=10] 0x3F 0x3F Ext. Crystal Osc.; Frequency 8.0- MHz; Start-up time: 16K CK + 65 ms; [CKSEL=1111 SUT=11] 8 OCDEN Enable OCD 1 JTAGEN Enable JTAG 0 SPIEN Enable Serial programming and Data Downloading 0 WDTON Watchdog timer always on 1 EESAVE EEPROM memory is preserved through chip erase 1 BOOTSZ1 Select Boot Size 0 BOOTSZ0 Select Boot Size 0 BOOTRST Select Reset Vector 1 10 0x80 0x00 On-Chip Debug Enabled; [OCDEN=0] 0x40 0x00 JTAG Interface Enabled; [JTAGEN=0] 0x20 0x00 Serial program downloading (SPI) enabled; [SPIEN=0] 0x10 0x00 Watchdog timer always on; [WDTON=0] 0x08 0x00 Preserve EEPROM memory through the Chip Erase cycle; [EESAVE=0] 0x06 0x06 Boot Flash section size=256 words Boot start address=$3F00; [BOOTSZ=11] 0x06 0x04 Boot Flash section size=512 words Boot start address=$3E00; [BOOTSZ=10] 0x06 0x02 Boot Flash section size=1024 words Boot start address=$3C00; [BOOTSZ=01] 0x06 0x00 Boot Flash section size=2048 words Boot start address=$3800; [BOOTSZ=00] ; default value 0x01 0x00 Boot Reset vector Enabled (default address=$0000); [BOOTRST=0] 3 BODLEVEL1 Brown-out Detector trigger level 1 BODLEVEL0 Brown-out Detector trigger level 1 RSTDISBL Reset disable fuse 1 5 0x0E 0x0E Brown-out detection disabled; [BODLEVEL=111] 0x0E 0x0C Brown-out detection level at VCC=1.8 V; [BODLEVEL=110] 0x0E 0x0A Brown-out detection level at VCC=2.7 V; [BODLEVEL=101] 0x0E 0x08 Brown-out detection level at VCC=4.3 V; [BODLEVEL=100] 0x01 0x00 External Reset Disable ATmega329P 16MHZ 1 RELEASED $1E $95 $03 [TIMER_COUNTER_0:TIMER_COUNTER_1:TIMER_COUNTER_2:WATCHDOG:EEPROM:SPI:PORTA:PORTB:PORTC:PORTD:ANALOG_COMPARATOR:PORTE:PORTF:PORTG:JTAG:EXTERNAL_INTERRUPT:USI:AD_CONVERTER:BOOT_LOAD:USART0:LCD:CPU] [TCCR0A:TCNT0:OCR0A:TIMSK0:TIFR0:GTCCR] io_timer.bmp At8pwm0_01 TCCR0A Timer/Counter0 Control Register $24 $44 io_flag.bmp Y FOC0A Force Output Compare The FOC0A bit is only active when the WGM bits specifies a non-PWM mode. However, for ensuring compatibility with future devices, this bit must be set to zero when TCCR0 is written when operating in PWM mode. When writing a logical one to the FOC0 bit, an immediate compare match is forced on the waveform generation unit. The OC0 output is changed accord-ing to its COM01:0 bits setting. Note that the FOC0 bit is implemented as a strobe. Therefore it is the value present in the COM01:0 bits that determines the effect of the forced compare. A FOC0 strobe will not generate any interrupt, nor will it clear the timer in CTC mode using OCR0 as TOP. The FOC0 bit is always read as ze W 0 WGM00 Waveform Generation Mode 0 These bits control the counting sequence of the counter, the source for the maximum (TOP) counter value, and what type of waveform generation to be used. Modes of operation supported by the Timer/Counter unit are: Normal mode, Clear Timer on Compare match (CTC) mode, and two types of Pulse Width Modulation (PWM) modes. See Table 51 and “Modes of Operation” on page 80. RW 0 COM0A1 Compare Match Output Mode 1 These bits control the output compare pin (OC0) behavior. If one or both of the COM01:0 bits are set, the OC0 output over-rides the normal port functionality of the I/O pin it is connected to. However, note that the Data Direction Register (DDR) bit corresponding to OC0 pin must be set in order to enable the output driver. When OC0 is connected to the pin, the function of the COM01:0 bits depends on the WGM01:0 bit setting. Table 52 shows the COM01:0 bit functionality when the WGM01:0 bits are set to a normal or CTC mode (non-PWM RW 0 COM0A0 Compare match Output Mode 0 These bits control the output compare pin (OC0) behavior. If one or both of the COM01:0 bits are set, the OC0 output over-rides the normal port functionality of the I/O pin it is connected to. However, note that the Data Direction Register (DDR) bit corresponding to OC0 pin must be set in order to enable the output driver. When OC0 is connected to the pin, the function of the COM01:0 bits depends on the WGM01:0 bit setting. Table 52 shows the COM01:0 bit functionality when the WGM01:0 bits are set to a normal or CTC mode (non-PWM) RW 0 WGM01 Waveform Generation Mode 1 These bits control the counting sequence of the counter, the source for the maximum (TOP) counter value, and what type of waveform generation to be used. Modes of operation supported by the Timer/Counter unit are: Normal mode, Clear Timer on Compare match (CTC) mode, and two types of Pulse Width Modulation (PWM) modes. See Table 51 and “Modes of Operation” on page 80. RW 0 CS02 Clock Select 2 The three clock select bits select the clock source to be used by the Timer/Counter, RW 0 CS01 Clock Select 1 The three clock select bits select the clock source to be used by the Timer/Counter, RW 0 CS00 Clock Select 1 The three clock select bits select the clock source to be used by the Timer/Counter, RW 0 TCNT0 Timer/Counter0 The Timer/Counter Register gives direct access, both for read and write operations, to the Timer/Counter unit 8-bit counter. Writing to the TCNT0 register blocks (removes) the compare match on the following timer clock. Modifying the counter (TCNT0) while the counter is running, introduces a risk of missing a compare match between TCNT0 the OCR0 register. $26 $46 io_timer.bmp N TCNT0_7 RW 0 TCNT0_6 RW 0 TCNT0_5 RW 0 TCNT0_4 RW 0 TCNT0_3 RW 0 TCNT0_2 RW 0 TCNT0_1 RW 0 TCNT0_0 RW 0 OCR0A Timer/Counter0 Output Compare Register The Output Compare Register contains an 8-bit value that is continuously compared with the counter value (TCNT0). A match can be used to generate an output compare interrupt, or to generate a waveform output on the OC0 pin. $27 $47 io_timer.bmp N OCR0A7 RW 0 OCR0A6 RW 0 OCR0A5 RW 0 OCR0A4 RW 0 OCR0A3 RW 0 OCR0A2 RW 0 OCR0A1 RW 0 OCR0A0 RW 0 TIMSK0 Timer/Counter0 Interrupt Mask Register NA $6E io_flag.bmp Y OCIE0A Timer/Counter0 Output Compare Match Interrupt Enable When the OCIE0 bit is written to one, and the I-bit in the Status Register is set (one), the Timer/Counter0 Compare Match interrupt is enabled. The corresponding interrupt is executed if a compare match in Timer/Counter0 occurs, i.e. when the OCF0 bit is set in the Timer/Counter Interrupt Flag Register - TIFR. RW 0 TOIE0 Timer/Counter0 Overflow Interrupt Enable When the TOIE0 bit is written to one, and the I-bit in the Status Register is set (one), the Timer/Counter0 Overflow interrupt is enabled. The corresponding interrupt is executed if an overflow in Timer/Counter0 occurs, i.e. when the TOV0 bit is set in the Timer/Counter Interrupt Flag Register - TIFR. RW 0 TIFR0 Timer/Counter0 Interrupt Flag register $15 $35 io_flag.bmp Y OCF0A Timer/Counter0 Output Compare Flag 0 The OCF0 bit is set (one) when a compare match occurs between the Timer/Counter0 and the data in OCR0 - Output Compare Register0. OCF0 is cleared by hardware when executing the corresponding interrupt handling vector. Alterna-tively, OCF0 is cleared by writing a logic one to the flag. When the I-bit in SREG, OCIE0 (Timer/Counter0 Compare match Interrupt Enable), and OCF0 are set (one), the Timer/Counter0 Compare match Interrupt is executed. RW 0 TOV0 Timer/Counter0 Overflow Flag The bit TOV0 is set (one) when an overflow occurs in Timer/Counter0. TOV0 is cleared by hardware when executing the corresponding interrupt handling vector. Alternatively, TOV0 is cleared by writing a logic one to the flag. When the SREG I-bit, TOIE0 (Timer/Counter0 Overflow Interrupt Enable), and TOV0 are set (one), the Timer/Counter0 Overflow interrupt is executed. In PWM mode, this bit is set when Timer/Counter0 changes counting direction at $00. RW 0 GTCCR General Timer/Control Register $23 $43 io_cpu.bmp Y TSM Timer/Counter Synchronization Mode R 0 PSR310 PSR10 PSR0 PSR1 PSR3 Prescaler Reset Timer/Counter1 and Timer/Counter0 When this bit is set (one)the Timer/Counter1 and Timer/Counter0 prescaler will be reset.The bit will be cleared by hard ware after the operation is performed.Writing a zero to this bit will have no effect.Note that Timer/Counter1 and Timer/Counter0 share the same prescaler and a reset of this prescaler will affect both timers.This bit will always be read as zero. RW 0 [TIMSK1:TIFR1:TCCR1A:TCCR1B:TCCR1C:TCNT1H:TCNT1L:OCR1AH:OCR1AL:OCR1BH:OCR1BL:ICR1H:ICR1L] [TCNT1H:TCNT1L];[OCR1AH:OCR1AL];[OCR1BH:OCR1BL];[ICR1H:ICR1L] io_timer.bmp t16pwm1_05.xml TCCR1A Timer/Counter1 Control Register A NA $80 io_flag.bmp Y COM1A1 Compare Output Mode 1A, bit 1 The COM1A1 and COM1A0 control bits determine any output pin action following a compare match in Timer/Counter1. Any output pin actions affect pin OC1A - Output CompareA. This is an alternative function to an I/O port, and the corresponding direction control bit must be set (one) to control an output pin. The control configuration is shown in Table 10. RW 0 COM1A0 Compare Output Mode 1A, bit 0 The COM1A1 and COM1A0 control bits determine any output pin action following a compare match in Timer/Counter1. Any output pin actions affect pin OC1A - Output CompareA. This is an alternative function to an I/O port, and the corresponding direction control bit must be set (one) to control an output pin. The control configuration is shown in Table 10. RW 0 COM1B1 Compare Output Mode 1B, bit 1 The COM1B1 and COM1B0 control bits determine any output pin action following a compare match in Timer/Counter1. Any output pin actions affect pin OC1B - Output CompareB. This is an alternative function to an I/O port, and the corre-sponding direction control bit must be set (one) to control an output pin. RW 0 COM1B0 Compare Output Mode 1B, bit 0 The COM1B1 and COM1B0 control bits determine any output pin action following a compare match in Timer/Counter1. Any output pin actions affect pin OC1B - Output CompareB. This is an alternative function to an I/O port, and the corre-sponding direction control bit must be set (one) to control an output pin. RW 0 WGM11 Waveform Generation Mode Combined with the WGM13:2 bits found in the TCCR1B register,these bits control the counting sequence of the counter, the source for maximum (TOP)counter value,and what type of waveform generation to be used.Modes of operation supported by the timer/counter unit are:Normal mode (counter),Clear Timer on Compare match (CTC)mode,and three types of Pulse Width Modulation (PWM)modes. PLease refer to the manual for a Mode Bit Description Table. RW 0 WGM10 Waveform Generation Mode Combined with the WGM13:2 bits found in the TCCR1B register,these bits control the counting sequence of the counter, the source for maximum (TOP)counter value,and what type of waveform generation to be used.Modes of operation supported by the timer/counter unit are:Normal mode (counter),Clear Timer on Compare match (CTC)mode,and three types of Pulse Width Modulation (PWM)modes. PLease refer to the manual for a Mode Bit Description Table. RW 0 TCCR1B Timer/Counter1 Control Register B NA $81 io_flag.bmp Y ICNC1 Input Capture 1 Noise Canceler When the ICNC1 bit is cleared (zero), the input capture trigger noise canceler function is disabled. The input capture is triggered at the first rising/falling edge sampled on the ICP - input capture pin - as specified. When the ICNC1 bit is set (one), four successive samples are measures on the ICP - input capture pin, and all samples must be high/low according to the input capture trigger specification in the ICES1 bit. The actual sampling frequency is XTAL clock frequency. RW 0 ICES1 Input Capture 1 Edge Select While the ICES1 bit is cleared (zero), the Timer/Counter1 contents are transferred to the Input Capture Register - ICR1 - on the falling edge of the input capture pin - ICP. While the ICES1 bit is set (one), the Timer/Counter1 contents are transferred to the Input Capture Register - ICR1 - on the rising edge of the input capture pin - ICP. RW 0 WGM13 Waveform Generation Mode Combined with the WGM13:2 bits found in the TCCR1B register,these bits control the counting sequence of the counter, the source for maximum (TOP)counter value,and what type of waveform generation to be used.Modes of operation supported by the timer/counter unit are:Normal mode (counter),Clear Timer on Compare match (CTC)mode,and three types of Pulse Width Modulation (PWM)modes. PLease refer to the manual for a Mode Bit Description Table. RW 0 WGM12 Waveform Generation Mode Combined with the WGM13:2 bits found in the TCCR1B register,these bits control the counting sequence of the counter, the source for maximum (TOP)counter value,and what type of waveform generation to be used.Modes of operation supported by the timer/counter unit are:Normal mode (counter),Clear Timer on Compare match (CTC)mode,and three types of Pulse Width Modulation (PWM)modes. PLease refer to the manual for a Mode Bit Description Table. RW 0 CS12 Prescaler source of Timer/Counter 1 Select Prescaling Clock Source of Timer/Counter1. (0:0:0) = Stop. (0:0:1) = CK. (0:1:0) = CK / 8. (0:1:1) = CK / 64. (1:0:0) = CK / 256. (1:0:1) = CK / 1024. (1:1:0) = External Pin T1, falling edge. (1:1:1) = External Pin 1, rising edge. RW 0 CS11 Prescaler source of Timer/Counter 1 Select Prescaling Clock Source of Timer/Counter1. (0:0:0) = Stop. (0:0:1) = CK. (0:1:0) = CK / 8. (0:1:1) = CK / 64. (1:0:0) = CK / 256. (1:0:1) = CK / 1024. (1:1:0) = External Pin T1, falling edge. (1:1:1) = External Pin 1, rising edge. RW 0 CS10 Prescaler source of Timer/Counter 1 Select Prescaling Clock Source of Timer/Counter1. (0:0:0) = Stop. (0:0:1) = CK. (0:1:0) = CK / 8. (0:1:1) = CK / 64. (1:0:0) = CK / 256. (1:0:1) = CK / 1024. (1:1:0) = External Pin T1, falling edge. (1:1:1) = External Pin 1, rising edge. RW 0 TCCR1C Timer/Counter 1 Control Register C NA $82 io_flag.bmp Y FOC1A Force Output Compare 1A Writing a logical one to this bit, forces a change in the compare match output pin PD5 according to the values already set in COM1A1 and COM1A0.If the COM1A1 and COM1A0 bits are written in the same cycle as FOC1A,the new settings will not take effect until next compare match or forced compare match occurs. The Force Output Compare bit can be used to change the output pin without waiting for a compare match in the timer. The automatic action programmed in COM1A1 and COM1A0 happens as if a Compare Match had occurred, but no interrupt is generated and it will not clear the timer even if CTC1 in TCCR1B is set. The corresponding I/O pin must be set as an output pin for the FOC1A bit to have effect on the pin. The FOC1A bit will always be read as zero. The setting of the FOC1A bit has no effect in PWM m RW 0 FOC1B Force Output Compare 1B Writing a logical one to this bit, forces a change in the compare match output pin PD4 according to the values already set in COM1B1 and COM1B0.If the COM1B1 and COM1B0 bits are written in the same cycle as FOC1B,the new settings will not take effect until next compare match or forced compare match occurs. The Force Output Compare bit can be used to change the output pin without waiting for a compare match in the timer. The automatic action programmed in COM1B1 and COM1B0 happens as if a Compare Match had occurred, but no interrupt is generated. The corresponding I/O pin must be set as an output pin for the FOC1B bit to have effect on the pin. The FOC1B bit will always be read as zero. The setting of the FOC1B bit has no effect in PWM mo RW 0 TCNT1H Timer/Counter1 High Byte This 16-bit register contains the prescaled value of the 16-bit Timer/Counter1. To ensure that both the high and low bytes are read and written simultaneously when the CPU accesses these registers, the access is performed using an 8-bit temporary register (TEMP). This temporary register is also used when accessing OCR1A, OCR1B and ICR1. If the main program and also interrupt routines perform access to registers using TEMP, interrupts must be disabled during access from the main program (and from interrupt routines if interrupts are allowed from within interrupt rou NA $85 io_timer.bmp N TCNT1H7 Timer/Counter1 High Byte bit 7 RW 0 TCNT1H6 Timer/Counter1 High Byte bit 6 RW 0 TCNT1H5 Timer/Counter1 High Byte bit 5 RW 0 TCNT1H4 Timer/Counter1 High Byte bit 4 RW 0 TCNT1H3 Timer/Counter1 High Byte bit 3 RW 0 TCNT1H2 Timer/Counter1 High Byte bit 2 RW 0 TCNT1H1 Timer/Counter1 High Byte bit 1 RW 0 TCNT1H0 Timer/Counter1 High Byte bit 0 RW 0 TCNT1L Timer/Counter1 Low Byte This 16-bit register contains the prescaled value of the 16-bit Timer/Counter1. To ensure that both the high and low bytes are read and written simultaneously when the CPU accesses these registers, the access is performed using an 8-bit temporary register (TEMP). This temporary register is also used when accessing OCR1A, OCR1B and ICR1. If the main program and also interrupt routines perform access to registers using TEMP, interrupts must be disabled during access from the main program (and from interrupt routines if interrupts are allowed from within interru NA $84 io_timer.bmp N TCNT1L7 Timer/Counter1 Low Byte bit 7 RW 0 TCNT1L6 Timer/Counter1 Low Byte bit 6 RW 0 TCNT1L5 Timer/Counter1 Low Byte bit 5 RW 0 TCNT1L4 Timer/Counter1 Low Byte bit 4 RW 0 TCNT1L3 Timer/Counter1 Low Byte bit 3 RW 0 TCNT1L2 Timer/Counter1 Low Byte bit 2 RW 0 TCNT1L1 Timer/Counter1 Low Byte bit 1 RW 0 TCNT1L0 Timer/Counter1 Low Byte bit 0 RW 0 OCR1AH Timer/Counter1 Outbut Compare Register A High Byte The output compare registers are 16-bit read/write registers. The Timer/Counter1 Output Compare Registers contain the data to be continuously compared with Timer/Counter1. Actions on compare matches are specified in the Timer/Counter1 Control and Status register.A compare match does only occur if Timer/Counter1 counts to the OCR value. A software write that sets TCNT1 and OCR1A or OCR1B to the same value does not generate a compare match. A compare match will set the compare interrupt flag in the CPU clock cycle following the compare event. Since the Output Compare Registers - OCR1A and OCR1B - are 16-bit registers, a temporary register TEMP is used when OCR1A/B are written to ensure that both bytes are updated simultaneously. When the CPU writes the high byte, OCR1AH or OCR1BH, the data is temporarily stored in the TEMP register. When the CPU writes the low byte, OCR1AL or OCR1BL, the TEMP register is simultaneously written to OCR1AH or OCR1BH. Consequently, the high byte OCR1AH or OCR1BH must be written first for a full 16-bit register write operation. The TEMP register is also used when accessing TCNT1, and ICR1. If the main program and also interrupt routines perform access to registers using TEMP, interrupts must be disabled during access from the main program (and from interrupt routines if interrupts are allowed from within interr NA $89 io_timer.bmp N OCR1AH7 Timer/Counter1 Outbut Compare Register High Byte bit 7 RW 0 OCR1AH6 Timer/Counter1 Outbut Compare Register High Byte bit 6 RW 0 OCR1AH5 Timer/Counter1 Outbut Compare Register High Byte bit 5 RW 0 OCR1AH4 Timer/Counter1 Outbut Compare Register High Byte bit 4 RW 0 OCR1AH3 Timer/Counter1 Outbut Compare Register High Byte bit 3 RW 0 OCR1AH2 Timer/Counter1 Outbut Compare Register High Byte bit 2 RW 0 OCR1AH1 Timer/Counter1 Outbut Compare Register High Byte bit 1 RW 0 OCR1AH0 Timer/Counter1 Outbut Compare Register High Byte bit 0 RW 0 OCR1AL Timer/Counter1 Outbut Compare Register A Low Byte The output compare registers are 16-bit read/write registers. The Timer/Counter1 Output Compare Registers contain the data to be continuously compared with Timer/Counter1. Actions on compare matches are specified in the Timer/Counter1 Control and Status register.A compare match does only occur if Timer/Counter1 counts to the OCR value. A software write that sets TCNT1 and OCR1A or OCR1B to the same value does not generate a compare match. A compare match will set the compare interrupt flag in the CPU clock cycle following the compare event. Since the Output Compare Registers - OCR1A and OCR1B - are 16-bit registers, a temporary register TEMP is used when OCR1A/B are written to ensure that both bytes are updated simultaneously. When the CPU writes the high byte, OCR1AH or OCR1BH, the data is temporarily stored in the TEMP register. When the CPU writes the low byte, OCR1AL or OCR1BL, the TEMP register is simultaneously written to OCR1AH or OCR1BH. Consequently, the high byte OCR1AH or OCR1BH must be written first for a full 16-bit register write operation. The TEMP register is also used when accessing TCNT1, and ICR1. If the main program and also interrupt routines perform access to registers using TEMP, interrupts must be disabled during access from the main program (and from interrupt routines if interrupts are allowed from within interru NA $88 io_timer.bmp N OCR1AL7 Timer/Counter1 Outbut Compare Register Low Byte Bit 7 RW 0 OCR1AL6 Timer/Counter1 Outbut Compare Register Low Byte Bit 6 RW 0 OCR1AL5 Timer/Counter1 Outbut Compare Register Low Byte Bit 5 RW 0 OCR1AL4 Timer/Counter1 Outbut Compare Register Low Byte Bit 4 RW 0 OCR1AL3 Timer/Counter1 Outbut Compare Register Low Byte Bit 3 RW 0 OCR1AL2 Timer/Counter1 Outbut Compare Register Low Byte Bit 2 RW 0 OCR1AL1 Timer/Counter1 Outbut Compare Register Low Byte Bit 1 RW 0 OCR1AL0 Timer/Counter1 Outbut Compare Register Low Byte Bit 0 RW 0 OCR1BH Timer/Counter1 Output Compare Register B High Byte The output compare registers are 16-bit read/write registers. The Timer/Counter1 Output Compare Registers contain the data to be continuously compared with Timer/Counter1. Actions on compare matches are specified in the Timer/Counter1 Control and Status register.A compare match does only occur if Timer/Counter1 counts to the OCR value. A software write that sets TCNT1 and OCR1A or OCR1B to the same value does not generate a compare match. A compare match will set the compare interrupt flag in the CPU clock cycle following the compare event. Since the Output Compare Registers - OCR1A and OCR1B - are 16-bit registers, a temporary register TEMP is used when OCR1A/B are written to ensure that both bytes are updated simultaneously. When the CPU writes the high byte, OCR1AH or OCR1BH, the data is temporarily stored in the TEMP register. When the CPU writes the low byte, OCR1AL or OCR1BL, the TEMP register is simultaneously written to OCR1AH or OCR1BH. Consequently, the high byte OCR1AH or OCR1BH must be written first for a full 16-bit register write operation. The TEMP register is also used when accessing TCNT1, and ICR1. If the main program and also interrupt routines perform access to registers using TEMP, interrupts must be disabled during access from the main program (and from interrupt routines if interrupts are allowed from within interrupt r NA $8B io_timer.bmp N OCR1BH7 Timer/Counter1 Output Compare Register High Byte bit 7 RW 0 OCR1BH6 Timer/Counter1 Output Compare Register High Byte bit 6 RW 0 OCR1BH5 Timer/Counter1 Output Compare Register High Byte bit 5 RW 0 OCR1BH4 Timer/Counter1 Output Compare Register High Byte bit 4 RW 0 OCR1BH3 Timer/Counter1 Output Compare Register High Byte bit 3 RW 0 OCR1BH2 Timer/Counter1 Output Compare Register High Byte bit 2 RW 0 OCR1BH1 Timer/Counter1 Output Compare Register High Byte bit 1 RW 0 OCR1BH0 Timer/Counter1 Output Compare Register High Byte bit 0 RW 0 OCR1BL Timer/Counter1 Output Compare Register B Low Byte The output compare registers are 16-bit read/write registers. The Timer/Counter1 Output Compare Registers contain the data to be continuously compared with Timer/Counter1. Actions on compare matches are specified in the Timer/Counter1 Control and Status register.A compare match does only occur if Timer/Counter1 counts to the OCR value. A software write that sets TCNT1 and OCR1A or OCR1B to the same value does not generate a compare match. A compare match will set the compare interrupt flag in the CPU clock cycle following the compare event. Since the Output Compare Registers - OCR1A and OCR1B - are 16-bit registers, a temporary register TEMP is used when OCR1A/B are written to ensure that both bytes are updated simultaneously. When the CPU writes the high byte, OCR1AH or OCR1BH, the data is temporarily stored in the TEMP register. When the CPU writes the low byte, OCR1AL or OCR1BL, the TEMP register is simultaneously written to OCR1AH or OCR1BH. Consequently, the high byte OCR1AH or OCR1BH must be written first for a full 16-bit register write operation. The TEMP register is also used when accessing TCNT1, and ICR1. If the main program and also interrupt routines perform access to registers using TEMP, interrupts must be disabled during access from the main program (and from interrupt routines if interrupts are allowed from within interrupt rout NA $8A io_timer.bmp N OCR1BL7 Timer/Counter1 Output Compare Register Low Byte bit 7 R 0 OCR1BL6 Timer/Counter1 Output Compare Register Low Byte bit 6 RW 0 OCR1BL5 Timer/Counter1 Output Compare Register Low Byte bit 5 RW 0 OCR1BL4 Timer/Counter1 Output Compare Register Low Byte bit 4 RW 0 OCR1BL3 Timer/Counter1 Output Compare Register Low Byte bit 3 RW 0 OCR1BL2 Timer/Counter1 Output Compare Register Low Byte bit 2 RW 0 OCR1BL1 Timer/Counter1 Output Compare Register Low Byte bit 1 RW 0 OCR1BL0 Timer/Counter1 Output Compare Register Low Byte bit 0 RW 0 ICR1H Timer/Counter1 Input Capture Register High Byte The input capture register is a 16-bit read-only register. When the rising or falling edge (according to the input capture edge setting - ICES1) of the signal at the input capture pin -ICP - is detected, the current value of the Timer/Counter1 is transferred to the Input Capture Register - ICR1. At the same time, the input capture flag - ICF1 - is set (one). Since the Input Capture Register - ICR1 - is a 16-bit register, a temporary register TEMP is used when ICR1 is read to ensure that both bytes are read simultaneously. When the CPU reads the low byte ICR1L, the data is sent to the CPU and the data of the high byte ICR1H is placed in the TEMP register. When the CPU reads the data in the high byte ICR1H, the CPU receives the data in the TEMP register. Consequently, the low byte ICR1L must be accessed first for a full 16-bit register read operation. The TEMP register is also used when accessing TCNT1, OCR1A and OCR1B. If the main program and also interrupt routines perform access to registers using TEMP, interrupts must be disabled during access from the main program (and from interrupt routines if interrupts are allowed from within interrupt NA $87 io_timer.bmp N ICR1H7 Timer/Counter1 Input Capture Register High Byte bit 7 RW 0 ICR1H6 Timer/Counter1 Input Capture Register High Byte bit 6 R 0 ICR1H5 Timer/Counter1 Input Capture Register High Byte bit 5 R 0 ICR1H4 Timer/Counter1 Input Capture Register High Byte bit 4 R 0 ICR1H3 Timer/Counter1 Input Capture Register High Byte bit 3 R 0 ICR1H2 Timer/Counter1 Input Capture Register High Byte bit 2 R 0 ICR1H1 Timer/Counter1 Input Capture Register High Byte bit 1 R 0 ICR1H0 Timer/Counter1 Input Capture Register High Byte bit 0 R 0 ICR1L Timer/Counter1 Input Capture Register Low Byte The input capture register is a 16-bit read-only register. When the rising or falling edge (according to the input capture edge setting - ICES1) of the signal at the input capture pin -ICP - is detected, the current value of the Timer/Counter1 is transferred to the Input Capture Register - ICR1. At the same time, the input capture flag - ICF1 - is set (one). Since the Input Capture Register - ICR1 - is a 16-bit register, a temporary register TEMP is used when ICR1 is read to ensure that both bytes are read simultaneously. When the CPU reads the low byte ICR1L, the data is sent to the CPU and the data of the high byte ICR1H is placed in the TEMP register. When the CPU reads the data in the high byte ICR1H, the CPU receives the data in the TEMP register. Consequently, the low byte ICR1L must be accessed first for a full 16-bit register read operation. The TEMP register is also used when accessing TCNT1, OCR1A and OCR1B. If the main program and also interrupt routines perform access to registers using TEMP, interrupts must be disabled during access from the main program (and from interrupt routines if interrupts are allowed from within inter NA $86 io_timer.bmp N ICR1L7 Timer/Counter1 Input Capture Register Low Byte bit 7 R 0 ICR1L6 Timer/Counter1 Input Capture Register Low Byte bit 6 R 0 ICR1L5 Timer/Counter1 Input Capture Register Low Byte bit 5 R 0 ICR1L4 Timer/Counter1 Input Capture Register Low Byte bit 4 R 0 ICR1L3 Timer/Counter1 Input Capture Register Low Byte bit 3 R 0 ICR1L2 Timer/Counter1 Input Capture Register Low Byte bit 2 R 0 ICR1L1 Timer/Counter1 Input Capture Register Low Byte bit 1 R 0 ICR1L0 Timer/Counter1 Input Capture Register Low Byte bit 0 R 0 TIMSK1 Timer/Counter1 Interrupt Mask Register NA $6F io_flag.bmp Y ICIE1 Timer/Counter1 Input Capture Interrupt Enable When the TICIE1 bit is set (one) and the I-bit in the Status Register is set (one), the Timer/Counter1 Input Capture Event Interrupt is enabled. The corresponding interrupt (at vector $003) is executed if a capture-triggering event occurs on pin 31, ICP, i.e., when the ICF1 bit is set in the Timer/Counter Interrupt Flag Register - TIFR. RW 0 OCIE1B Timer/Counter1 Output Compare B Match Interrupt Enable When the OCIE1B bit is set (one) and the I-bit in the Status Register is set (one), the Timer/Counter1 CompareB Match interrupt is enabled. The corresponding interrupt (at vector $005) is executed if a CompareB match in Timer/Counter1 occurs, i.e., when the OCF1B bit is set in the Timer/Counter Interrupt Flag Register - TIFR. R 0 OCIE1A Timer/Counter1 Output Compare A Match Interrupt Enable When the OCIE1A bit is set (one) and the I-bit in the Status Register is set (one), the Timer/Counter1 CompareA Match interrupt is enabled. The corresponding interrupt (at vector $004) is executed if a CompareA match in Timer/Counter1 occurs, i.e., when the OCF1A bit is set in the Timer/Counter Interrupt Flag Register - TIFR. RW 0 TOIE1 Timer/Counter1 Overflow Interrupt Enable When the TOIE1 bit is set (one) and the I-bit in the Status Register is set (one), the Timer/Counter1 Overflow interrupt is enabled. The corresponding interrupt (at vector $006) is executed if an overflow in Timer/Counter1 occurs, i.e., when the TOV1 bit is set in the Timer/Counter Interrupt Flag Register - TIFR. RW 0 TIFR1 Timer/Counter1 Interrupt Flag register $16 $36 io_flag.bmp Y ICF1 Input Capture Flag 1 The ICF1 bit is set (one) to flag an input capture event, indicating that the Timer/Counter1 value has been transferred to the input capture register - ICR1. ICF1 is cleared by hardware when executing the corresponding interrupt handling vector. Alternatively, ICF1 is cleared by writing a logic one to the flag. When the SREG I-bit, and TICIE1 (Timer/Counter1 Input Capture Interrupt Enable), and ICF1 are set (one), the Timer/Counter1 Capture Interrupt is executed. RW 0 OCF1B Output Compare Flag 1B The OCF1B bit is set (one) when compare match occurs between the Timer/Counter1 and the data in OCR1B - Output Compare Register 1B. OCF1B is cleared by hardware when executing the corresponding interrupt handling vector. Alterna-tively, OCF1B is cleared by writing a logic one to the flag. When the I-bit in SREG, and OCIE1B (Timer/Counter1 Compare match InterruptB Enable), and the OCF1B are set (one), the Timer/Counter1 Compare B match Interrupt is executed. RW 0 OCF1A Output Compare Flag 1A The OCF1A bit is set (one) when compare match occurs between the Timer/Counter1 and the data in OCR1A - Output Compare Register 1A. OCF1A is cleared by hardware when executing the corresponding interrupt handling vector. Alterna-tively, OCF1A is cleared by writing a logic one to the flag. When the I-bit in SREG, and OCIE1A (Timer/Counter1 Compare match InterruptA Enable), and the OCF1A are set (one), the Timer/Counter1 Compare A match Interrupt is executed. RW 0 TOV1 Timer/Counter1 Overflow Flag The TOV1 is set (one) when an overflow occurs in Timer/Counter1. TOV1 is cleared by hardware when executing the cor-responding interrupt handling vector. Alternatively, TOV1 is cleared by writing a logic one to the flag. When the I-bit in SREG, and TOIE1 (Timer/Counter1 Overflow Interrupt Enable), and TOV1 are set (one), the Timer/Counter1 Overflow Interrupt is executed. In PWM mode, this bit is set when Timer/Counter1 changes counting direction at $0000. RW 0 [TIMSK2:TIFR2:TCCR2A:TCNT2:OCR2A:GTCCR:ASSR] io_timer.bmp At8pwm2_02 The 8-bit Timer/Counter2 can select clock source from CK, prescaled CK, or external crystal input TOSC1. It can also be stopped as described in the section “Timer/Counter2 Control Register - TCCR2”. The status flags (overflow and compare match) are found in the Timer/Counter Interrupt Flag Register - TIFR. Control signals are found in the Timer/Counter Control Register TCCR2. The interrupt enable/disable settings are found in “The Timer/Counter Interrupt Mask Register - TIMSK”. When Timer/Counter2 is externally clocked, the external signal is synchronized with the oscillator frequency of the CPU. To assure proper sampling of the external clock, the minimum time between two external clock transitions must be at least one internal CPU clock period. The external clock signal is sampled on the rising edge of the internal CPU clock. This module features a high resolution and a high accuracy usage with the lower prescaling opportunities. Similarly, the high prescaling opportunities make this unit useful for lower speed functions or exact timing functions with infrequent actions. Timer/Counter2 can also be used as an 8-bit Pulse Width Modulator. In this mode, Timer/Counter2 and the output compare register serve as a glitch-free, stand-alone PWM with centered puls TCCR2A Timer/Counter2 Control Register NA $B0 io_flag.bmp Y FOC2A Force Output Compare A Writing a logical one to this bit, forces a change in the compare match output pin OC2 according to the values already set in COM21 and COM20. If the COM21 and COM20 bits are written in the same cycle as FOC2, the new settings will not take effect until next compare match or forced output compare match occurs. The Force Output Compare bit can be used to change the output pin without waiting for a compare match in the timer. The automatic action programmed in COM21 and COM20 happens as if a Compare Match had occurred, but no interrupt is generated, and the Timer/Counter will not be cleared even if CTC2 is set. The corresponding I/O pin must be set as an output pin for the FOC2 bit to have effect on the pin. The FOC2 bit will always be read as zero. Setting the FOC2 bit has no effect in PWM mod RW 0 WGM20 Waveform Generation Mode These bits control the counting sequence of the counter,the source for hte maximum (TOP)counter value,and what type of waveform generation to be used.Modes of operation supported by the timer/counter unit are:Normal mode (counter), Clear Timer on Compare match (CTC)mode,and two types of Pulse Width Modulation (PWM)modes. Please refer to the manual for more information. RW 0 COM2A1 Compare Output Mode bit 1 The COM21 and COM20 control bits determine any output pin action following a compare match in Timer/Counter2. Output pin actions affect pin PD7(OC2). This is an alternative function to an I/O port, and the corresponding direction control bit must be set (one) to control an output pin. (COM21:COM20) description: (0:0) = Timer/Counter disconnected from output pin OC2. (0:1) = Toggle the OC2 output line. (1:0) = Clear the OC2 output line (to zero). (1:1) = Set the OC2 output line (to one). Note: In PWM mode, these bits have a different function RW 0 COM2A0 Compare Output Mode bit 0 The COM21 and COM20 control bits determine any output pin action following a compare match in Timer/Counter2. Output pin actions affect pin PD7(OC2). This is an alternative function to an I/O port, and the corresponding direction control bit must be set (one) to control an output pin. (COM21:COM20) description: (0:0) = Timer/Counter disconnected from output pin OC2. (0:1) = Toggle the OC2 output line. (1:0) = Clear the OC2 output line (to zero). (1:1) = Set the OC2 output line (to one). Note: In PWM mode, these bits have a different function RW 0 WGM21 Waveform Generation Mode These bits control the counting sequence of the counter,the source for hte maximum (TOP)counter value,and what type of waveform generation to be used.Modes of operation supported by the timer/counter unit are:Normal mode (counter), Clear Timer on Compare match (CTC)mode,and two types of Pulse Width Modulation (PWM)modes. Please refer to the manual for more information. RW 0 CS22 Clock Select bit 2 The Clock Select bits 2,1, and 0 define the prescaling source of Timer/Counter2. (CS22:CS21:CS20) Description. (0:0:0) Timer/Counter2 is stopped. (0:0:1) PCK2. (0:1:0) PCK2/8. (0:1:1) PCK2/32. (1:0:0) PCK2/64. (1:0:1) PCK2/128. (1:1:0) PCK2/256. (1:1:1) PCK2/1024. The Stop condition provides a Timer Enable/Disable function. The prescaled modes are scaled directly from the PCK2 clock. RW 0 CS21 Clock Select bit 1 The Clock Select bits 2,1, and 0 define the prescaling source of Timer/Counter2. (CS22:CS21:CS20) Description. (0:0:0) Timer/Counter2 is stopped. (0:0:1) PCK2. (0:1:0) PCK2/8. (0:1:1) PCK2/32. (1:0:0) PCK2/64. (1:0:1) PCK2/128. (1:1:0) PCK2/256. (1:1:1) PCK2/1024. The Stop condition provides a Timer Enable/Disable function. The prescaled modes are scaled directly from the PCK2 clock. RW 0 CS20 Clock Select bit 0 The Clock Select bits 2,1, and 0 define the prescaling source of Timer/Counter2. (CS22:CS21:CS20) Description. (0:0:0) Timer/Counter2 is stopped. (0:0:1) PCK2. (0:1:0) PCK2/8. (0:1:1) PCK2/32. (1:0:0) PCK2/64. (1:0:1) PCK2/128. (1:1:0) PCK2/256. (1:1:1) PCK2/1024. The Stop condition provides a Timer Enable/Disable function. The prescaled modes are scaled directly from the PCK2 clock. RW 0 TCNT2 Timer/Counter2 This 8-bit register contains the value of Timer/Counter2. Timer/Counters2 is implemented as an up or up/down (in PWM mode) counter with read and write access. If the Timer/Counter2iswritten to and a clocksourceisselected,it continues counting in the timer clock cycle following the write operation. NA $B2 io_timer.bmp N TCNT2-7 Timer/Counter 2 bit 7 RW 0 TCNT2-6 Timer/Counter 2 bit 6 RW 0 TCNT2-5 Timer/Counter 2 bit 5 RW 0 TCNT2-4 Timer/Counter 2 bit 4 RW 0 TCNT2-3 Timer/Counter 2 bit 3 RW 0 TCNT2-2 Timer/Counter 2 bit 2 RW 0 TCNT2-1 Timer/Counter 2 bit 1 RW 0 TCNT2-0 Timer/Counter 2 bit 0 RW 0 OCR2A Timer/Counter2 Output Compare Register The output compare register is an 8-bit read/write register. The Timer/Counter Output Compare Register contains the data to be continuously compared with Timer/Counter2. Actions on compare matches are specified in TCCR2. A compare match does only occur if Timer/Counter2 counts to the OCR2 value. A software write that sets TCNT2 and OCR2 to the same value does not generate a compare match. A compare match will set the compare interrupt flag in the CPU clock cycle following the compare event. Timer/Counter2 in PWM Mode When PWM mode is selected, the Timer/Counter2 either wraps (overflows) when it reaches $FF or it acts as an up/down counter. If the up/down mode is selected, the Timer/Counter2 and the Output Compare Register - OCR2 form an 8-bit, free-running, glitch-free, and phase correct PWM with outputs on the PD7(OC2) pin. If the overflow mode is selected, the Timer/Counter2 and the Output Compare Register - OCR2 form an 8-bit, free-running, and glitch-free PWM, operating with twice the speed of the up/down counting mode. PWM Modes (Up/Down and Overflow). The two different PWM modes are selected by the CTC2 bit in the Timer/Counter Control Register - TCCR2. If CTC2 is cleared and PWM mode is selected, the Timer/Counter acts as an up/down counter, counting up from $00 to $FF, where it turns and counts down again to zero before the cycle is repeated. When the counter value matches the con-tents of the Output Compare Register, the PD7(OC2) pin is set or cleared according to the settings of the COM21/COM20 bits in the Timer/Counter Control Register TCCR2. If CTC2 is set and PWM mode is selected, the Timer/Counters will wrap and start counting from $00 after reaching $FF. The PD7(OC2) pin will be set or cleared according to the settings of COM21/COM20 on a Timer/Counter overflow or when the counter value matches the contents of the Output Compare Register. Note that in PWM mode, the value to be written to the Output Compare Register is first transferred to a temporary location, and then latched into OCR2 when the Timer/Counter reaches $FF. This prevents the occurrence of odd-length PWM pulses (glitches) in the event of an unsynchronized OCR2 write. (CTC2:COM21:COM20) Effect on Compare Pin Frequency: (0:0:0) = Not connected. (0:0:1) = Not connected. (0:1:0) = Cleared on compare match, up-counting. Set on compare match, down-counting (non-inverted PWM). f TCK0/2 /510. (0:1:1) = Cleared on compare match, down-counting. Set on compare match, up-counting (inverted PWM). f TCK0/2 /510. (1:0:0) = Not connected. (1:0:1) = Not connected. (1:1:0) = Cleared on compare match, set on overflow. f TCK0/2 /256. (1:1:1) = Set on compare match, cleared on overflow. f TCK0/ NA $B3 io_timer.bmp N OCR2A7 Timer/Counter2 Output Compare Register Bit 7 RW 0 OCR2A6 Timer/Counter2 Output Compare Register Bit 6 RW 0 OCR2A5 Timer/Counter2 Output Compare Register Bit 5 RW 0 OCR2A4 Timer/Counter2 Output Compare Register Bit 4 RW 0 OCR2A3 Timer/Counter2 Output Compare Register Bit 3 RW 0 OCR2A2 Timer/Counter2 Output Compare Register Bit 2 RW 0 OCR2A1 Timer/Counter2 Output Compare Register Bit 1 RW 0 OCR2A0 Timer/Counter2 Output Compare Register Bit 0 RW 0 TIMSK2 Timer/Counter2 Interrupt Mask register NA $70 io_flag.bmp Y OCIE2A Timer/Counter2 Output Compare Match Interrupt Enable When the OCIE2 bit is set (one) and the I-bit in the Status Register is set (one), the Timer/Counter2 Compare Match interrupt is enabled. The corresponding interrupt (at vector $006) is executed if a compare match in Timer/Counter2 occurs, i.e. when the OCF2 bit is set in the Timer/Counter Interrupt Flag Register - TIFR. RW 0 TOIE2 Timer/Counter2 Overflow Interrupt Enable When the TOIE2 bit is set (one) and the I-bit in the Status Register is set (one), the Timer/Counter2 Overflow interrupt is RW 0 TIFR2 Timer/Counter2 Interrupt Flag Register $17 $37 io_flag.bmp Y OCF2A Timer/Counter2 Output Compare Flag 2 The OCF2 bit is set (one) when a compare match occurs between the Timer/Counter2 and the data in OCR2 - Output Compare Register2. OCF2 is cleared by hardware when executing the corresponding interrupt handling vector. Alternatively, OCF2 is cleared by writing a logic one to the flag. When the I-bit in SREG, and OCIE2 (Timer/Counter2 Compare match Interrupt Enable), and the OCF2 are set (one), the Timer/Counter2 Compare match Interrupt is executed. RW 0 TOV2 Timer/Counter2 Overflow Flag The TOV2 bit is set (one) when an overflow occurs in Timer/Counter2. TOV2 is cleared by hardware when executing the corresponding interrupt handling vector. Alternatively, TOV2 is cleared by writing a logic one to the flag. When the SREG I-bit, and TOIE2 (Timer/Counter2 Overflow Interrupt Enable), and TOV2 are set (one), the Timer/Counter2 Overflow interrupt is executed. In up/down PWM mode, this bit is set when Timer/Counter2 changes counting direction at $00. RW 0 GTCCR General Timer/Counter Control Register $23 $43 io_cpu.bmp Y PSR2 Prescaler Reset Timer/Counter2 When this bit is set (one)the Timer/Counter2 prescaler will be reset.The bit will be cleared by hardware after the operation is performed.Writing a zero to this bit will have no effect.This bit will always be read as zero if Timer/Counter2 is clocked by the internal CPU clock.If this bit is written when Timer/Counter2 is operating in asynchronous mode,the bit will remain one until the prescaler has been reset. R 0 ASSR Asynchronous Status Register NA $B6 io_flag.bmp Y EXCLK Enable External Clock Interrupt When EXCLK is written to one, and asynchronous clock is selected, the external clock input buffer is enabled and an external clock can be input on Timer Oscillator 1 (TOSC1) pin instead of a 32 kHz crystal. Writing to EXCLK should be done before asynchronous operation is selected. Note that the crystal Oscillator will only run when this bit is zero. RW 0 AS2 AS2: Asynchronous Timer/Counter2 When AS2 is written to zero, Timer/Counter2 is clocked from the I/O clock, clk I/O . When AS2 is written to one, Timer/Counter2 is clocked from a crystal Oscillator connected to the Timer Oscillator 1 (TOSC1) pin. When the value of AS2 is changed, the contents of TCNT2, OCR2A, and TCCR2A might be corrupted. RW 0 TCN2UB TCN2UB: Timer/Counter2 Update Busy When Timer/Counter2 operates asynchronously and TCNT2 is written, this bit becomes set. When TCNT2 has been updated from the temporary storage register, this bit is cleared by hardware. A logical zero in this bit indicates that TCNT2 is ready to be updated with a new value. R 0 OCR2UB Output Compare Register2 Update Busy When Timer/Counter2 operates asynchronously and OCR2A is written, this bit becomes set. When OCR2A has been updated from the temporary storage register, this bit is cleared by hardware. A logical zero in this bit indicates that OCR2A is ready to be updated with a new value. R 0 TCR2UB TCR2UB: Timer/Counter Control Register2 Update Busy When Timer/Counter2 operates asynchronously and TCCR2A is written, this bit becomes set. When TCCR2A has been updated from the temporary storage register, this bit is cleared by hardware. A logical zero in this bit indicates that TCCR2A is ready to be updated with a new value. If a write is performed to any of the three Timer/Counter2 Registers while its update busy flag is set, the updated value might get corrupted and cause an unintentional inter-rupt to occur. The mechanisms for reading TCNT2, OCR2A, and TCCR2A are different. When read-ing TCNT2, the actual timer value is read. When reading OCR2A or TCCR2A, the value in the temporary storage register is r R 0 [WDTCR] io_watch.bmp WDTCR WDTCSR Watchdog Timer Control Register NA $60 io_flag.bmp Y WDCE WDTOE Watchdog Change Enable This bit must be set when the WDE bit is written to logic zero.Otherwise,the watchdog will not be disabled.Once written to one,hardware will clear this bit after four clock cycles.Refer to the description of the WDE bit for a watchdog disable procedure.This bit must also be set when changing the prescaler bits. RW 0 WDE Watch Dog Enable When the WDE is set (one) the Watchdog Timer is enabled, and if the WDE is cleared (zero) the Watchdog Timer function is disabled. WDE can only be cleared if the WDTOE bit is set(one). To disable an enabled watchdog timer, the following procedure must be followed: 1. In the same operation, write a logical one to WDTOE and WDE. A logical one must be written to WDE even though it is set to one before the disable operation starts. 2. Within the next four clock cycles, write a logical 0 to WDE. This disables the watchdog RW 0 WDP2 Watch Dog Timer Prescaler bit 2 The WDP2,WDP1,and WDP0 bits determine the Watchdog Timer prescaling when the Watchdog Timer is enabled. RW 0 WDP1 Watch Dog Timer Prescaler bit 1 The WDP2,WDP1,and WDP0 bits determine the Watchdog Timer prescaling when the Watchdog Timer is enabled. RW 0 WDP0 Watch Dog Timer Prescaler bit 0 The WDP2,WDP1,and WDP0 bits determine the Watchdog Timer prescaling when the Watchdog Timer is enabled. RW 0 [EEARH:EEARL:EEDR:EECR] [EEARH:EEARL] io_cpu.bmp EEPROM Read/Write Access. The EEPROM access registers are accessible in the I/O space. The write access time for the EEPROM is given in Table 1. A self-timing function, however, lets the user software detect when the next byte can be written. If the user code contains instructions that write the EEPROM, some precautions must be taken. In heavily filtered power supplies, V CC is likely to rise or fall slowly on power-up/down. This causes the device for some period of time to run at a voltage lower than specified as minimum for the clock frequency used. See “Preventing EEPROM Corruption” on page 19. for details on how to avoid problems in these situations.In order to prevent unintentional EEPROM writes, a specific write procedure must be followed. Refer to the description of the EEPROM Control Register for details on this. When the EEPROM is read, the CPU is halted for four clock cycles before the next instruction is executed. When theEEPROM is written, the CPU is halted for two clock cycles before the next instruction is execute EEARH EEPROM Read/Write Access High Byte Bits 9..0 - EEAR9..0: EEPROM Address The EEPROM Address Registers - EEARH and EEARL specify the EEPROM address in the 1K bytes EEPROM space. The EEPROM data bytes are addressed linearly between 0 and 1023. The initial value of EEAR is undefined. A proper value must be written before the EEPROM may be accessed. $22 $42 io_cpu.bmp N EEAR9 EEPROM Read/Write Access Bit 9 RW 0 EEAR8 EEPROM Read/Write Access Bit 8 RW 0 EEARL EEPROM Read/Write Access Low Byte Bits 9..0 - EEAR9..0: EEPROM Address The EEPROM Address Registers - EEARH and EEARL specify the EEPROM address in the 1K bytes EEPROM space. The EEPROM data bytes are addressed linearly between 0 and 1023. The initial value of EEAR is undefined. A proper value must be written before the EEPROM may be accessed. $21 $41 io_cpu.bmp N EEAR7 EEPROM Read/Write Access Bit 7 RW 0 EEAR6 EEPROM Read/Write Access Bit 6 RW 0 EEAR5 EEPROM Read/Write Access Bit 5 RW 0 EEAR4 EEPROM Read/Write Access Bit 4 RW 0 EEAR3 EEPROM Read/Write Access Bit 3 RW 0 EEAR2 EEPROM Read/Write Access Bit 2 RW 0 EEAR1 EEPROM Read/Write Access Bit 1 RW 0 EEAR00 EEPROM Read/Write Access Bit 0 RW 0 EEDR EEPROM Data Register For the EEPROM write operation, the EEDR register contains the data to be written to the EEPROM in the address given by the EEAR register. For the EEPROM read operation, the EEDR contains the data read out from the EEPROM at the address given by EEAR. $20 $40 io_cpu.bmp N EEDR7 EEPROM Data Register bit 7 RW 0 EEDR6 EEPROM Data Register bit 6 RW 0 EEDR5 EEPROM Data Register bit 5 RW 0 EEDR4 EEPROM Data Register bit 4 RW 0 EEDR3 EEPROM Data Register bit 3 RW 0 EEDR2 EEPROM Data Register bit 2 RW 0 EEDR1 EEPROM Data Register bit 1 RW 0 EEDR0 EEPROM Data Register bit 0 RW 0 EECR EEPROM Control Register $1F $3F io_flag.bmp Y EERIE EEPROM Ready Interrupt Enable EEPROM Ready Interrupt Enable Writing EERIE to one enables the EEPROM Ready Interrupt if the I bit in SREG is set. Writing EERIE to zero disables the interrupt. The EEPROM Ready interrupt generates a constant interrupt when EEWE is cleared. RW 0 EEMWE EEPROM Master Write Enable The EEMWE bit determines whether setting EEWE to one causes the EEPROM to be written. When EEMWE is written to one, writing EEWE to one within 4 clock cycles will write data to the EEPROM at the selected address. If EEMWE is zero, writing EEWE to one will have no effect. When EEMWE has been written to one by software, hardware clears the bit to zero after four clock cycles. See the description of the EEWE bit for an EEPROM write procedure. RW 0 EEWE EEPROM Write Enable The EEPROM Write Enable Signal EEWE is the write strobe to the EEPROM. When address and data are correctly set up, the EEWE bit must be set to write the value into the EEPROM. The EEMWE bit must be set when the logical one is written to EEWE, otherwise no EEPROM write takes place. The following procedure should be followed when writing the EEPROM (the order of steps 3 and 4 is not essential): 1. Wait until EEWE becomes zero. 2. Wait until SPMEN in SPMCR becomes zero. 3. Write new EEPROM address to EEAR (optional). 4. Write new EEPROM data to EEDR (optional). 5. Write a logical one to the EEMWE bit while writing a zero to EEWE in EECR. 6. Within four clock cycles after setting EEMWE, write a logical one to EEWE. The EEPROM can not be programmed during a CPU write to the Flash memory. The software must check that the Flash programming is completed before initiating a new EEPROM write. Step 2 is only relevant if the software contains a boot loader allowing the CPU to program the Flash. If the Flash is never being updated by the CPU, step 2 can be omitted. See “Boot Loader Support - Read While Write self-programming” on page 228 for details about boot programming. Caution: An interrupt between step 5 and step 6 will make the write cycle fail, since the EEPROM Master Write Enable will time-out. If an interrupt routine accessing the EEPROM is interrupting another EEPROM access, the EEAR or EEDR regis-ter will be modified, causing the interrupted EEPROM access to fail. It is recommended to have the global interrupt flag cleared during the 4 last steps to avoid these problems. When the write access time has elapsed, the EEWE bit is cleared by hardware. The user software can poll this bit and wait for a zero before writing the next byte. When EEWE has been set, the CPU is halted for two cycles before the next instruction is exec RW X EERE EEPROM Read Enable The EEPROM Read Enable Signal EERE is the read strobe to the EEPROM. When the correct address is set up in the EEAR register, the EERE bit must be written to a logic one to trigger the EEPROM read. The EEPROM read access takes one instruction, and the requested data is available immediately. When the EEPROM is read, the CPU is halted for four cycles before the next instruction is executed. The user should poll the EEWE bit before starting the read operation. If a write operation is in progress, it is neither possible to read the EEPROM, nor to change the EEAR register. The calibrated oscillator is used to time the EEPROM accesses. Table 1 lists the typical programming time for EEPROM access from the CPU RW 0 [SPDR:SPSR:SPCR] io_com.bmp The Serial Peripheral Interface(SPI) allows high-speed synchronous data transfer between the AT90S4414/8515 and peripheral devices or between several AVR devices. The AT90S4414/8515 SPI features include the following: • Full-duplex, 3-wire Synchronous Data Transfer • Master or Slave Operation • LSB First or MSB First Data Transfer • Four Programmable Bit Rates • End of Transmission Interrupt Flag • Write Collision Flag Protection • Wakeup from Idle Mode (Slave Mode Only) SPCR SPI Control Register $2C $4C io_flag.bmp Y SPIE SPI Interrupt Enable This bit causes the SPI interrupt to be executed if SPIF bit in the SPSR register is set and the global interrupts are enabled. RW 0 SPE SPI Enable When the SPE bit is set (one), the SPI is enabled. This bit must be set to enable any SPI operations. RW 0 DORD Data Order When the DORD bit is set (one), the LSB of the data word is transmitted first. When the DORD bit is cleared (zero), the MSB of the data word is transmitted first. RW 0 MSTR Master/Slave Select This bit selects Master SPI mode when set (one), and Slave SPI mode when cleared (zero). If SS is configured as an input and is driven low while MSTR is set, MSTR will be cleared, and SPIF in SPSR will become set. The user will then have to set MSTR to re-enable SPI master mode. RW 0 CPOL Clock polarity When this bit is set (one), SCK is high when idle. When CPOL is cleared (zero), SCK is low when idle. Refer to Figure 36 and Figure 37 for additional information. RW 0 CPHA Clock Phase Refer to Figure 36 or Figure 37 for the functionality of this bit. RW 0 SPR1 SPI Clock Rate Select 1 These two bits control the SCK rate of the device configured as a master. SPR1 and SPR0 have no effect on the slave. RW 0 SPR0 SPI Clock Rate Select 0 These two bits control the SCK rate of the device configured as a master. SPR1 and SPR0 have no effect on the slave. RW 0 SPSR SPI Status Register $2D $4D io_flag.bmp Y SPIF SPI Interrupt Flag When a serial transfer is complete, the SPIF bit is set (one) and an interrupt is generated if SPIE in SPCR is set (one) and global interrupts are enabled. If SS is an input and is driven low when the SPI is in master mode, this will also set the SPIF flag. SPIF is cleared by hardware when executing the corresponding interrupt handling vector. Alternatively, the SPIF bit is cleared by first reading the SPI status register when SPIF is set (one), then accessing the SPI Data Register (SPDR). R 0 WCOL Write Collision Flag The WCOL bit is set if the SPI data register (SPDR) is written during a data transfer. The WCOL bit (and the SPIF bit) are cleared (zero) by first reading the SPI Status Register when WCOL is set (one), and then accessing the SPI Data Register. R 0 SPI2X Double SPI Speed Bit When this bit is written logic one the SPI speed (SCK Frequency)will be doubled when the SPI is in master mode .This means that the minimum SCK period will be 2 CPU clock periods.When the SPI is configured as Slave,the SPI is only guaranteed to work at f osc /4orlower. The SPI interface on the ATmega162 is also used for program memory and EEPROM downloading or uploading. RW 0 SPDR SPI Data Register The SPI Data Register is a read/write register used for data transfer between the register file and the SPI Shift register. Writing to the register initiates data transmission. Reading the register causes the Shift Register Receive buffer to be read. $2E $4E io_com.bmp N SPDR7 SPI Data Register bit 7 RW X SPDR6 SPI Data Register bit 6 RW X SPDR5 SPI Data Register bit 5 RW X SPDR4 SPI Data Register bit 4 RW X SPDR3 SPI Data Register bit 3 RW X SPDR2 SPI Data Register bit 2 RW X SPDR1 SPI Data Register bit 1 R 0 SPDR0 SPI Data Register bit 0 R 0 [PORTA:DDRA:PINA] io_port.bmp AVRSimIOPort.SimIOPort PORTA Port A Data Register $02 $22 io_port.bmp N PORTA7 Port A Data Register bit 7 RW 0 PORTA6 Port A Data Register bit 6 RW 0 PORTA5 Port A Data Register bit 5 RW 0 PORTA4 Port A Data Register bit 4 RW 0 PORTA3 Port A Data Register bit 3 RW 0 PORTA2 Port A Data Register bit 2 RW 0 PORTA1 Port A Data Register bit 1 RW 0 PORTA0 Port A Data Register bit 0 RW 0 DDRA Port A Data Direction Register $01 $21 io_flag.bmp N DDA7 Data Direction Register, Port A, bit 7 RW 0 DDA6 Data Direction Register, Port A, bit 6 RW 0 DDA5 Data Direction Register, Port A, bit 5 RW 0 DDA4 Data Direction Register, Port A, bit 4 RW 0 DDA3 Data Direction Register, Port A, bit 3 RW 0 DDA2 Data Direction Register, Port A, bit 2 RW 0 DDA1 Data Direction Register, Port A, bit 1 RW 0 DDA0 Data Direction Register, Port A, bit 0 RW 0 PINA Port A Input Pins The Port A Input Pins address - PINA - is not a register, and this address enables access to the physical value on each Port A pin. When reading PORTA the Port A Data Latch is read, and when reading PINA, the logical values present on the pins are read. $00 $20 io_port.bmp N PINA7 Input Pins, Port A bit 7 RW Hi-Z PINA6 Input Pins, Port A bit 6 RW Hi-Z PINA5 Input Pins, Port A bit 5 RW Hi-Z PINA4 Input Pins, Port A bit 4 RW Hi-Z PINA3 Input Pins, Port A bit 3 RW Hi-Z PINA2 Input Pins, Port A bit 2 RW Hi-Z PINA1 Input Pins, Port A bit 1 RW Hi-Z PINA0 Input Pins, Port A bit 0 RW Hi-Z [PORTB:DDRB:PINB] io_port.bmp AVRSimIOPort.SimIOPort PORTB Port B Data Register $05 $25 io_port.bmp N PORTB7 Port B Data Register bit 7 RW 0 PORTB6 Port B Data Register bit 6 RW 0 PORTB5 Port B Data Register bit 5 RW 0 PORTB4 Port B Data Register bit 4 RW 0 PORTB3 Port B Data Register bit 3 RW 0 PORTB2 Port B Data Register bit 2 RW 0 PORTB1 Port B Data Register bit 1 RW 0 PORTB0 Port B Data Register bit 0 RW 0 DDRB Port B Data Direction Register $04 $24 io_flag.bmp N DDB7 Port B Data Direction Register bit 7 RW 0 DDB6 Port B Data Direction Register bit 6 RW 0 DDB5 Port B Data Direction Register bit 5 RW 0 DDB4 Port B Data Direction Register bit 4 RW 0 DDB3 Port B Data Direction Register bit 3 RW 0 DDB2 Port B Data Direction Register bit 2 RW 0 DDB1 Port B Data Direction Register bit 1 RW 0 DDB0 Port B Data Direction Register bit 0 RW 0 PINB Port B Input Pins The Port B Input Pins address - PINB - is not a register, and this address enables access to the physical value on each Port B pin. When reading PORTB, the Port B Data Latch is read, and when reading PINB, the logical values present on the pins are read. $03 $23 io_port.bmp N PINB7 Port B Input Pins bit 7 R 0 PINB6 Port B Input Pins bit 6 R 0 PINB5 Port B Input Pins bit 5 R 0 PINB4 Port B Input Pins bit 4 R 0 PINB3 Port B Input Pins bit 3 R 0 PINB2 Port B Input Pins bit 2 R 0 PINB1 Port B Input Pins bit 1 R 0 PINB0 Port B Input Pins bit 0 R 0 [PORTC:DDRC:PINC] io_port.bmp AVRSimIOPort.SimIOPort PORTC Port C Data Register $08 $28 io_port.bmp N PORTC7 Port C Data Register bit 7 RW 0 PORTC6 Port C Data Register bit 6 RW 0 PORTC5 Port C Data Register bit 5 RW 0 PORTC4 Port C Data Register bit 4 RW 0 PORTC3 Port C Data Register bit 3 RW 0 PORTC2 Port C Data Register bit 2 RW 0 PORTC1 Port C Data Register bit 1 RW 0 PORTC0 Port C Data Register bit 0 RW 0 DDRC Port C Data Direction Register $07 $27 io_flag.bmp N DDC7 Port C Data Direction Register bit 7 RW 0 DDC6 Port C Data Direction Register bit 6 RW 0 DDC5 Port C Data Direction Register bit 5 RW 0 DDC4 Port C Data Direction Register bit 4 RW 0 DDC3 Port C Data Direction Register bit 3 RW 0 DDC2 Port C Data Direction Register bit 2 RW 0 DDC1 Port C Data Direction Register bit 1 RW 0 DDC0 Port C Data Direction Register bit 0 RW 0 PINC Port C Input Pins The Port C Input Pins address - PINC - is not a register, and this address enables access to the physical value on each Port C pin. When reading PORTC, the Port C Data Latch is read, and when reading PINC, the logical values present on the pins are read. $06 $26 io_port.bmp N PINC7 Port C Input Pins bit 7 R 0 PINC6 Port C Input Pins bit 6 R 0 PINC5 Port C Input Pins bit 5 R 0 PINC4 Port C Input Pins bit 4 R 0 PINC3 Port C Input Pins bit 3 R 0 PINC2 Port C Input Pins bit 2 R 0 PINC1 Port C Input Pins bit 1 R 0 PINC0 Port C Input Pins bit 0 R 0 [PORTD:DDRD:PIND] io_port.bmp AVRSimIOPort.SimIOPort PORTD Port D Data Register $0B $2B io_port.bmp N PORTD7 Port D Data Register bit 7 RW 0 PORTD6 Port D Data Register bit 6 RW 0 PORTD5 Port D Data Register bit 5 RW 0 PORTD4 Port D Data Register bit 4 RW 0 PORTD3 Port D Data Register bit 3 RW 0 PORTD2 Port D Data Register bit 2 RW 0 PORTD1 Port D Data Register bit 1 RW 0 PORTD0 Port D Data Register bit 0 RW 0 DDRD Port D Data Direction Register $0A $2A io_flag.bmp N DDD7 Port D Data Direction Register bit 7 RW 0 DDD6 Port D Data Direction Register bit 6 RW 0 DDD5 Port D Data Direction Register bit 5 RW 0 DDD4 Port D Data Direction Register bit 4 RW 0 DDD3 Port D Data Direction Register bit 3 RW 0 DDD2 Port D Data Direction Register bit 2 RW 0 DDD1 Port D Data Direction Register bit 1 RW 0 DDD0 Port D Data Direction Register bit 0 RW 0 PIND Port D Input Pins The Port D Input Pins address - PIND - is not a register, and this address enables access to the physical value on each Port D pin. When reading PORTD, the Port D Data Latch is read, and when reading PIND, the logical values present on the pins are read. $09 $29 io_port.bmp N PIND7 Port D Input Pins bit 7 R 0 PIND6 Port D Input Pins bit 6 R 0 PIND5 Port D Input Pins bit 5 R 0 PIND4 Port D Input Pins bit 4 R 0 PIND3 Port D Input Pins bit 3 R 0 PIND2 Port D Input Pins bit 2 R 0 PIND1 Port D Input Pins bit 1 R 0 PIND0 Port D Input Pins bit 0 R 0 [ADCSRB:ACSR:DIDR1] io_analo.bmp AlgComp_01 ADCSRB ADC Control and Status Register B NA $7B io_flag.bmp Y ACME Analog Comparator Multiplexer Enable When this bit is written logic one and the ADC is switched off (ADEN in ADCSR is zero), the ADC multiplexer selects the negative input to the Analog Comparator. When this bit is written logic zero, AIN1 is applied to the negative input of the Analog Comparator. For a detailed description of this bit, see “Analog Comparator Multiplexed Input” on page 186. RW 0 ACSR Analog Comparator Control And Status Register $30 $50 io_analo.bmp Y ACD Analog Comparator Disable When this bit is written logic one, the power to the analog comparator is switched off. This bit can be set at any time to turn off the analog comparator. This will reduce power consumption in active and idle mode. When changing the ACD bit, the Analog Comparator Interrupt must be disabled by clearing the ACIE bit in ACSR. Otherwise an interrupt can occur when the bit is changed. RW 0 ACBG Analog Comparator Bandgap Select When this bit is set, a fixed bandgap reference voltage replaces the positive input to the Analog Comparator. When this bit is cleared, AIN0 is applied to the positive input of the Analog Comparator. See “Internal Voltage Reference” on page 42. RW 0 ACO Analog Compare Output The output of the analog comparator is synchronized and then directly connected to ACO. The synchronization introduces a delay of 1-2 clock cycles. R NA ACI Analog Comparator Interrupt Flag This bit is set by hardware when a comparator output event triggers the interrupt mode defined by ACIS1 and ACIS0. The Analog Comparator Interrupt routine is executed if the ACIE bit is set and the I-bit in SREG is set. ACI is cleared by hard-ware when executing the corresponding interrupt handling vector. Alternatively, ACI is cleared by writing a logic one to the flag. RW 0 ACIE Analog Comparator Interrupt Enable When the ACIE bit is written logic one and the I-bit in the Status Register is set, the analog comparator interrupt is acti-vated. When written logic zero, the interrupt is disabled. RW 0 ACIC Analog Comparator Input Capture Enable When written logic one, this bit enables the Input Capture function in Timer/Counter1 to be triggered by the analog comparator. The comparator output is in this case directly connected to the Input Capture front-end logic, making the comparator utilize the noise canceler and edge select features of the Timer/Counter1 Input Capture interrupt. When written logic zero, no connection between the analog comparator and the Input Capture function exists. To make the comparator trigger the Timer/Counter1 Input Capture interrupt, the TICIE1 bit in the Timer Interrupt Mask Register (TIMSK) must be set RW 0 ACIS1 Analog Comparator Interrupt Mode Select bit 1 These bits determine which comparator events that trigger the Analog Comparator interrupt. RW 0 ACIS0 Analog Comparator Interrupt Mode Select bit 0 These bits determine which comparator events that trigger the Analog Comparator interrupt. RW 0 DIDR1 Digital Input Disable Register 1 NA $7F io_analo.bmp Y AIN1D AIN1 Digital Input Disable When this bit is written logic one,the digital input buffer on the AIN1/0 pin is disabled.The corresponding PIN register bit will always read as zero when this bit is set.When an analog signal is applied to the AIN1/0 pin and the digital input from this pin is not needed,this bit should be written logic one to reduce power consumption in the digital input buffer. RW 0 AIN0D AIN0 Digital Input Disable When this bit is written logic one,the digital input buffer on the AIN1/0 pin is disabled.The corresponding PIN register bit will always read as zero when this bit is set.When an analog signal is applied to the AIN1/0 pin and the digital input from this pin is not needed,this bit should be written logic one to reduce power consumption in the digital input buffer. RW 0 [PORTE:DDRE:PINE] io_port.bmp AVRSimIOPort.SimIOPort PORTE Data Register, Port E $0E $2E io_port.bmp N PORTE7 RW 0 PORTE6 RW 0 PORTE5 RW 0 PORTE4 RW 0 PORTE3 RW 0 PORTE2 RW 0 PORTE1 RW 0 PORTE0 RW 0 DDRE Data Direction Register, Port E $0D $2D io_flag.bmp N DDE7 RW 0 DDE6 RW 0 DDE5 RW 0 DDE4 RW 0 DDE3 RW 0 DDE2 RW 0 DDE1 RW 0 DDE0 RW 0 PINE Input Pins, Port E $0C $2C io_port.bmp N PINE7 R 0 PINE6 R 0 PINE5 R 0 PINE4 R 0 PINE3 R 0 PINE2 R 0 PINE1 R 0 PINE0 R 0 [PORTF:DDRF:PINF] io_port.bmp AVRSimIOPort.SimIOPort PORTF Data Register, Port F $11 $31 io_port.bmp N PORTF7 RW 0 PORTF6 RW 0 PORTF5 RW 0 PORTF4 RW 0 PORTF3 RW 0 PORTF2 RW 0 PORTF1 RW 0 PORTF0 RW 0 DDRF Data Direction Register, Port F $10 $30 io_flag.bmp N DDF7 RW 0 DDF6 RW 0 DDF5 RW 0 DDF4 RW 0 DDF3 RW 0 DDF2 RW 0 DDF1 RW 0 DDF0 RW 0 PINF Input Pins, Port F $0F $2F io_port.bmp N PINF7 R 0 PINF6 R 0 PINF5 R 0 PINF4 R 0 PINF3 R 0 PINF2 R 0 PINF1 R 0 PINF0 R 0 [PORTG:DDRG:PING] io_port.bmp AVRSimIOPort.SimIOPort PORTG Port G Data Register $14 $34 io_port.bmp N PORTG4 RW 0 PORTG3 RW 0 PORTG2 RW 0 PORTG1 RW 0 PORTG0 RW 0 DDRG Port G Data Direction Register $13 $33 io_flag.bmp N DDG4 RW 0 DDG3 RW 0 DDG2 RW 0 DDG1 RW 0 DDG0 RW 0 PING Port G Input Pins $12 $32 io_port.bmp N PING5 R 0 PING4 R 0 PING3 R 0 PING2 R 0 PING1 R 0 PING0 R 0 [OCDR:MCUCR:MCUSR] io_com.bmp 00 JTAG Features: JTAG (IEEE std. 1149.1 compliant) Interface. Boundary-Scan Capabilities According to the IEEE std. 1149.1 (JTAG) Standard. Debugger Access to: – All Internal Peripheral Units – Internal and External RAM – The Internal Register File –Program Counter – EEPROM and Flash Memories. Extensive On-Chip Debug Support for Break Conditions, Including: –AVR Break Instruction – Break on Change of Program Memory Flow –Single Step Break –Program Memory Breakpoints on Single Address or Address Range – Data Memory Breakpoints on Single Address or Address Range. Programming of Flash, EEPROM, Fuses, and Lock Bits through the JTAG Interface. On-Chip Debugging Supported by AVR Stu OCDR On-Chip Debug Related Register in I/O Memory The OCDR register provides a communication channel from the running program in the microcontroller to the debugger. The CPU can transfer a byte to the debugger by writing to this location. At the same time, an internal flag; I/O Debug Reg-ister Dirty - IDRD - is set to indicate to the debugger that the register has been written. When the CPU reads the OCDR reg-ister the 7 LSB will be from the OCDR register, while the MSB is the IDRD bit. The debugger clears the IDRD bit when it has read the information. In some AVR devices, this register is shared with a standard I/O location. In this case, the OCDR register can only be accessed if the OCDEN fuse is programmed, and the debugger enables access to the OCDR register. In all other cases, the standard I/O location is accessed. Refer to the debugger documentation for further information on how to use this registe $31 $51 io_com.bmp N OCDR7 IDRD On-Chip Debug Register Bit 7 RW 0 OCDR6 On-Chip Debug Register Bit 6 RW 0 OCDR5 On-Chip Debug Register Bit 5 RW 0 OCDR4 On-Chip Debug Register Bit 4 RW 0 OCDR3 On-Chip Debug Register Bit 3 RW 0 OCDR2 On-Chip Debug Register Bit 2 RW 0 OCDR1 On-Chip Debug Register Bit 1 RW 0 OCDR0 On-Chip Debug Register Bit 0 RW 0 MCUCR MCU Control Register The MCU Control Register contains control bits for general MCU functions. $35 $55 io_flag.bmp Y JTD JTAG Interface Disable When this bit is written to zero, the JTAG interface is enabled if the JTAGEN fuse is programmed. If this bit is written to one, the JTAG interface is disabled. In order to avoid unintentional disabling or enabling of the JTAG interface, a timed sequence must be followed: The application software must write this to the desired value twice within four cycles to change the bit. RW 0 MCUSR MCU Status Register The MCU Status Register provides information on which reset source caused an MCU reset. $34 $54 io_flag.bmp Y JTRF JTAG Reset Flag This bit is set if a reset is being caused by a logic one in the JTAG Reset Register selected by the JTAG instruction AVR_RESET.This bit is reset by a Power-on reset,or by writing a logic zero to the flag. RW 0 [EICRA:EIMSK:EIFR:PCMSK1:PCMSK0] [PCMSK1:PCMSK0] io_ext.bmp The external interrupts are triggered by the INT7:0 pins. Observe that, if enabled, the interrupts will trigger even if the INT7:0 pins are configured as outputs. This feature provides a way of generating a software interrupt. The external inter-rupts can be triggered by a falling or rising edge or a low level. This is set up as indicated in the specification for the Exter-nal Interrupt Control Registers - EICRA (INT3:0) and EICRB (INT7:4). When the external interrupt is enabled and is configured as level triggered, the interrupt will trigger as long as the pin is held low. Note that recognition of falling or rising edge interrupts on INT7:4 requires the presence of an I/O clock, described in “Clock Systems and their Distribution” on page 29. Low level interrupts and the edge interrupt on INT3:0 are detected asynchronously. This implies that these inter-rupts can be used for waking the part also from sleep modes other than Idle mode. The I/O clock is halted in all sleep modes except Idle mode. Note that if a level triggered interrupt is used for wake-up from Power Down Mode, the changed level must be held for some time to wake up the MCU. This makes the MCU less sensitive to noise. The changed level is sampled twice by the watchdog oscillator clock. The period of the watchdog oscillator is 1 µs (nominal) at 5.0V and 25°C. The frequency of the watchdog oscillator is voltage dependent as shown in the Electrical Characteristics section. The MCU will wake up if the input has the required level during this sampling or if it is held until the end of the start-up time. The start-up time is defined by the SUT fuses as described in “Clock Systems and their Distribution” on page 29. If the level is sampled twice by the watchdog oscillator clock but disappears before the end of the start-up time, the MCU will still wake up, but no interrupt will be generated. The required level must be held long enough for the MCU to complete the wake up to trigger the level int EICRA External Interrupt Control Register A The External Interrupt Control Register A contains control bits for interrupt sense control. NA $69 io_flag.bmp Y ISC01 External Interrupt Sense Control 0 Bit 1 The External Interrupt 0 is activated by the external pin INT0 if the SREG I-flag and the corresponding interrupt mask are set.The value on the INT0 pin is sampled before detecting edges. If edge or toggle interrupt is selected, pulses that last longer than one clock period will generate an interrupt. Shorter pulses are not guaranteed to generate an interrupt. If low level interrupt is selected,the low level must be held until the completion of the currently executing instruction to generate an interrupt. RW 0 ISC00 External Interrupt Sense Control 0 Bit 0 The External Interrupt 0 is activated by the external pin INT0 if the SREG I-flag and the corresponding interrupt mask are set.The value on the INT0 pin is sampled before detecting edges. If edge or toggle interrupt is selected, pulses that last longer than one clock period will generate an interrupt. Shorter pulses are not guaranteed to generate an interrupt. If low level interrupt is selected,the low level must be held until the completion of the currently executing instruction to generate an interrupt. RW 0 EIMSK External Interrupt Mask Register $1D $3D io_flag.bmp Y PCIE3 Pin Change Interrupt Enable 3 When the PCIE3 bit is set (one) and the I-bit in the Status Register (SREG) is set (one), pin change interrupt 3 is enabled. Any change on any enabled PCINT30..24 pin will cause an interrupt. The corresponding interrupt of Pin Change Interrupt Request is executed from the PCINT3 interrupt Vector. PCINT30..24 pins are enabled individually by the PCMSK3 Register. This bit is reserved bit in ATmega329/649 and should always be written to zero. RW 0 PCIE2 Pin Change Interrupt Enable 2 When the PCIE2 bit is set (one) and the I-bit in the Status Register (SREG) is set (one), pin change interrupt 2 is enabled. Any change on any enabled PCINT23..16 pin will cause an interrupt. The corresponding interrupt of Pin Change Interrupt Request is executed from the PCINT2 interrupt Vector. PCINT23..16 pins are enabled individually by the PCMSK2 Register. This bit is reserved bit in ATmega329/649 and should always be written to zero. RW 0 PCIE1 Pin Change Interrupt Enable 1 When the PCIE1 bit is set (one) and the I-bit in the Status Register (SREG) is set (one), pin change interrupt 1 is enabled. Any change on any enabled PCINT15..8 pin will cause an interrupt. The corresponding interrupt of Pin Change Interrupt Request is executed from the PCINT1 interrupt Vector. PCINT15..8 pins are enabled individually by the PCMSK1 Register. PCIE0 Pin Change Interrupt Enable 0 When the PCIE0 bit is set (one) and the I-bit in the Status Register (SREG) is set (one), pin change interrupt 0 is enabled. Any change on any enabled PCINT7..0 pin will cause an interrupt. The corresponding interrupt of Pin Change Interrupt Request is executed from the PCINT0 interrupt Vector. PCINT7..0 pins are enabled individually by the PCMSK0 Register. RW 0 INT0 External Interrupt Request 0 Enable When the INT0 bit is set (one) and the I-bit in the Status Register (SREG) is set (one), the external pin interrupt is enabled. The Interrupt Sense Control0 bits 1/0 (ISC01 and ISC00) in the External Interrupt Control Register A (EICRA) define whether the external interrupt is activated on rising and/or falling edge of the INT0 pin or level sensed. Activity on the pin will cause an interrupt request even if INT0 is configured as an output.The corresponding interrupt of External Interrupt Request 0 is executed from the INT0 Interrupt Vector. RW 0 EIFR External Interrupt Flag Register $1C $3C io_flag.bmp Y PCIF3 Pin Change Interrupt Flag 3 When a logic change on any PCINT30..24 pin triggers an interrupt request, PCIF3 becomes set (one). If the I-bit in SREG and the PCIE3 bit in EIMSK are set (one), the MCU will jump to the corresponding Interrupt Vector. The flag is cleared when the interrupt routine is executed. Alternatively, the flag can be cleared by writing a logical one to it. This bit is reserved bit in ATmega329/649 and will always be read as zero. RW 0 PCIF2 Pin Change Interrupt Flag 2 When a logic change on any PCINT23..16 pin triggers an interrupt request, PCIF2 becomes set (one). If the I-bit in SREG and the PCIE2 bit in EIMSK are set (one), the MCU will jump to the corresponding Interrupt Vector. The flag is cleared when the interrupt routine is executed. Alternatively, the flag can be cleared by writing a logical one to it. This bit is reserved bit in ATmega329/649 and will always be read as zero. RW 0 PCIF1 Pin Change Interrupt Flag 1 When a logic change on any PCINT15..8 pin triggers an interrupt request, PCIF1 becomes set (one). If the I-bit in SREG and the PCIE1 bit in EIMSK are set (one), the MCU will jump to the corresponding Interrupt Vector. The flag is cleared when the interrupt routine is executed. Alternatively, the flag can be cleared by writing a logical one to it. RW 0 PCIF0 Pin Change Interrupt Flag 0 When a logic change on any PCINT7..0 pin triggers an interrupt request, PCIF0 becomes set (one). If the I-bit in SREG and the PCIE0 bit in EIMSK are set (one), the MCU will jump to the corresponding Interrupt Vector. The flag is cleared when the interrupt routine is executed. Alternatively, the flag can be cleared by writing a logical one to it. RW 0 INTF0 External Interrupt Flag 0 When an edge or logic change on the INT0 pin triggers an interrupt request, INTF0 becomes set (one). If the I-bit in SREG and the INT0 bit in EIMSK are set (one), the MCU will jump to the corresponding Interrupt Vector. The flag is cleared when the interrupt routine is executed. Alternatively, the flag can be cleared by writing a logical one to it. This flag is always cleared when INT0 is configured as a level interrupt. RW 0 PCMSK1 Pin Change Mask Register 1 Each PCINT15..8 bit selects whether pin change interrupt is enabled on the corresponding I/O pin. If PCINT15..8 is set and the PCIE1 bit in EIMSK is set, pin change interrupt is enabled on the corresponding I/O pin. If PCINT15..8 is cleared, pin change interrupt on the corresponding I/O pin is disabled. NA $6C io_flag.bmp N PCINT15 Pin Change Enable Mask 15 RW 0 PCINT14 Pin Change Enable Mask 14 RW 0 PCINT13 Pin Change Enable Mask 13 RW 0 PCINT12 Pin Change Enable Mask 12 RW 0 PCINT11 Pin Change Enable Mask 11 RW 0 PCINT10 Pin Change Enable Mask 10 RW 0 PCINT9 Pin Change Enable Mask 9 RW 0 PCINT8 Pin Change Enable Mask 8 RW 0 PCMSK0 Pin Change Mask Register 0 Each PCINT bit selects whether pin change interrupt is enabled on the corresponding I/O pin. If PCINT7..0 is set and the PCIE0 bit in EIMSK is set, pin change interrupt is enabled on the corresponding I/O pin. If PCINT7..0 is cleared, pin change interrupt on the corresponding I/O pin is disabled. NA $6B io_flag.bmp N PCINT7 Pin Change Enable Mask 7 RW 0 PCINT6 Pin Change Enable Mask 6 RW 0 PCINT5 Pin Change Enable Mask 5 RW 0 PCINT4 Pin Change Enable Mask 4 RW 0 PCINT3 Pin Change Enable Mask 3 RW 0 PCINT2 Pin Change Enable Mask 2 RW 0 PCINT1 Pin Change Enable Mask 1 RW 0 PCINT0 Pin Change Enable Mask 0 RW 0 [USIDR:USISR:USICR] io_com.bmp Universal Serial Interface USIDR USI Data Register NA $BA io_com.bmp N USIDR7 USI Data Register bit 7 RW 0 USIDR6 USI Data Register bit 6 RW 0 USIDR5 USI Data Register bit 5 RW 0 USIDR4 USI Data Register bit 4 RW 0 USIDR3 USI Data Register bit 3 RW 0 USIDR2 USI Data Register bit 2 RW 0 USIDR1 USI Data Register bit 1 RW 0 USIDR0 USI Data Register bit 0 RW 0 USISR USI Status Register NA $B9 io_flag.bmp Y USISIF Start Condition Interrupt Flag RW 0 USIOIF Counter Overflow Interrupt Flag RW 0 USIPF Stop Condition Flag RW 1 USIDC Data Output Collision RW 0 USICNT3 USI Counter Value Bit 3 RW 0 USICNT2 USI Counter Value Bit 2 RW 0 USICNT1 USI Counter Value Bit 1 RW 0 USICNT0 USI Counter Value Bit 0 RW 0 USICR USI Control Register NA $B8 io_flag.bmp Y USISIE Start Condition Interrupt Enable RW 0 USIOIE Counter Overflow Interrupt Enable RW 0 USIWM1 USI Wire Mode Bit 1 RW 1 USIWM0 USI Wire Mode Bit 0 RW 0 USICS1 USI Clock Source Select Bit 1 RW 0 USICS0 USI Clock Source Select Bit 0 RW 0 USICLK Clock Strobe R 0 USITC Toggle Clock Port Pin W 0 [ADMUX:ADCSRA:ADCH:ADCL:ADCSRB:DIDR0] ((IF ADMUX.ADLAR = 1) LINK [ADCH(1:0):ADCL(7:0)]); (IF ADMUX.ADLAR = 0) LINK [ADCH(7:0):ADCL(7:6)]); io_analo.bmp AD Converter Feature list: 10-bit Resolution. 0.5 LSB Integral Non-Linearity. +-2 LSB Absolute Accuracy. TBD - 260 µs Conversion Time. Up to TBD kSPS at maximum resolution. 8 Multiplexed Single Ended Input Channels. 7 Differential input channels (TQFP package only). 2 Differential input channels with optional gain of 10x and 200x (TQFP package only). Optional left adjustment for ADC result readout. 0 - VCC ADC Input Voltage Range. Selectable 2.56 V ADC reference voltage. Free Running or Single Conversion Mode. Interrupt on ADC Conversion Complete. Sleep Mode Nois ADMUX The ADC multiplexer Selection Register These bits select the voltage reference for the ADC, as shown in Table 91. If these bits are changed during a conversion, the change will not go in effect until this conversion is complete (ADIF in ADCSR is set). If differential channels are used, the selected reference should not be closer to AV CC than indicated in Table 94 on page 200. The internal voltage reference options may not be used if an external reference voltage is being applied to the AREF pin. NA $7C io_analo.bmp Y REFS1 Reference Selection Bit 1 These bits select the voltage reference for the ADC, as shown in Table 91. If these bits are changed during a conversion, the change will not go in effect until this conversion is complete (ADIF in ADCSR is set). If differential channels are used, the selected reference should not be closer to AV CC than indicated in Table 94 on page 200. The internal voltage reference options may not be used if an external reference voltage is being applied to the AREF pin. RW 0 REFS0 Reference Selection Bit 0 These bits select the voltage reference for the ADC, as shown in Table 91. If these bits are changed during a conversion, the change will not go in effect until this conversion is complete (ADIF in ADCSR is set). If differential channels are used, the selected reference should not be closer to AV CC than indicated in Table 94 on page 200. The internal voltage reference options may not be used if an external reference voltage is being applied to the AREF pin. RW 0 ADLAR Left Adjust Result The ADLAR bit affects the presentation of the ADC conversion result in the ADC data register. If ADLAR is cleared, the result is right adjusted. If ADLAR is set, the result is left adjusted. Changing the ADLAR bit will affect the ADC data register immediately, regardless of any ongoing conversions. For a complete description of this bit, see “The ADC Data Register -ADCL and ADCH” on page 198. RW 0 MUX4 Analog Channel and Gain Selection Bits The value of these bits selects which combination of analog inputs are connected to the ADC. These bits also select the gain for the differential channels. See Table 92 for details. If these bits are changed during a conversion, the change will not go in effect until this conversion is complete (ADIF in ADCSR is set). RW 0 MUX3 Analog Channel and Gain Selection Bits The value of these bits selects which combination of analog inputs are connected to the ADC. These bits also select the gain for the differential channels. See Table 92 for details. If these bits are changed during a conversion, the change will not go in effect until this conversion is complete (ADIF in ADCSR is set). RW 0 MUX2 Analog Channel and Gain Selection Bits The value of these bits selects which combination of analog inputs are connected to the ADC. These bits also select the gain for the differential channels. See Table 92 for details. If these bits are changed during a conversion, the change will not go in effect until this conversion is complete (ADIF in ADCSR is set). RW 0 MUX1 Analog Channel and Gain Selection Bits The value of these bits selects which combination of analog inputs are connected to the ADC. These bits also select the gain for the differential channels. See Table 92 for details. If these bits are changed during a conversion, the change will not go in effect until this conversion is complete (ADIF in ADCSR is set). RW 0 MUX0 Analog Channel and Gain Selection Bits The value of these bits selects which combination of analog inputs are connected to the ADC. These bits also select the gain for the differential channels. See Table 92 for details. If these bits are changed during a conversion, the change will not go in effect until this conversion is complete (ADIF in ADCSR is set). RW 0 ADCSRA The ADC Control and Status register NA $7A io_flag.bmp Y ADEN ADC Enable Writing a logical ‘1’ to this bit enables the ADC. By clearing this bit to zero, the ADC is turned off. Turning the ADC off while a conversion is in progress, will terminate this conversion. RW 0 ADSC ADC Start Conversion In Single Conversion Mode, a logical ‘1’ must be written to this bit to start each conversion. In Free Running Mode, a logical ‘1’ must be written to this bit to start the first conversion. The first time ADSC has been written after the ADC has been enabled, or if ADSC is written at the same time as the ADC is enabled, an extended conversion will result. This extended conversion performs initialization of the ADC. ADSC will read as one as long as a conversion is in progress. When the conversion is complete, it returns to zero. When a dummy conversion precedes a real conversion, ADSC will stay high until the real conversion completes. Writing a 0 to this bit has no effect RW 0 ADATE ADC Auto Trigger Enable When this bit is written to one,Auto Triggering of the ADC is enabled.The ADC will start a conversion on a positive edge of the selected trigger signal.The trigger source is selected by setting the ADC Trigger Select bits,ADTS in ADCSRB. RW 0 ADIF ADC Interrupt Flag This bit is set (one) when an ADC conversion completes and the data registers are updated. The ADC Conversion Complete Interrupt is executed if the ADIE bit and the I-bit in SREG are set (one). ADIF is cleared by hardware when executing the corresponding interrupt handling vector. Alternatively, ADIF is cleared by writing a logical one to the flag. Beware that if doing a read-modify-write on ADCSR, a pending interrupt can be disabled. This also applies if the SBI and CBI instructions are used. RW 0 ADIE ADC Interrupt Enable When this bit is set (one) and the I-bit in SREG is set (one), the ADC Conversion Complete Interrupt is activated. RW 0 ADPS2 ADC Prescaler Select Bits These bits determine the division factor between the XTAL frequency and the input clock to the ADC. RW 0 ADPS1 ADC Prescaler Select Bits These bits determine the division factor between the XTAL frequency and the input clock to the ADC. RW 0 ADPS0 ADC Prescaler Select Bits These bits determine the division factor between the XTAL frequency and the input clock to the ADC. RW 0 ADCH ADC Data Register High Byte When an ADC conversion is complete, the result is found in these two registers. If differential channels are used, the result is presented in two’s complement form. The selected channel is differential if MUX4..0 are between ‘01000’ and ‘11101’, otherwise the selected channel is single ended. When ADCL is read, the ADC Data Register is not updated until ADCH is read. Consequently, if the result is left adjusted and no more than 8 bit precision (7 bit + sign bit for differential input channels) is required, it is sufficient to read ADCH. Otherwise, ADCL must be read first, then ADCH. The ADLAR bit in ADMUX, and the MUX4..0 bits in ADMUX affect the way the result is read from the registers. If ADLAR is set, the result is left adjusted. If ADLAR is cleared (default), the result is right adju NA $79 io_analo.bmp N ADCH7 ADC Data Register High Byte Bit 7 RW 0 ADCH6 ADC Data Register High Byte Bit 6 RW 0 ADCH5 ADC Data Register High Byte Bit 5 RW 0 ADCH4 ADC Data Register High Byte Bit 4 RW 0 ADCH3 ADC Data Register High Byte Bit 3 RW 0 ADCH2 ADC Data Register High Byte Bit 2 RW 0 ADCH1 ADC Data Register High Byte Bit 1 RW 0 ADCH0 ADC Data Register High Byte Bit 0 RW 0 ADCL ADC Data Register Low Byte When an ADC conversion is complete, the result is found in these two registers. If differential channels are used, the result is presented in two’s complement form. The selected channel is differential if MUX4..0 are between ‘01000’ and ‘11101’, otherwise the selected channel is single ended. When ADCL is read, the ADC Data Register is not updated until ADCH is read. Consequently, if the result is left adjusted and no more than 8 bit precision (7 bit + sign bit for differential input channels) is required, it is sufficient to read ADCH. Otherwise, ADCL must be read first, then ADCH. The ADLAR bit in ADMUX, and the MUX4..0 bits in ADMUX affect the way the result is read from the registers. If ADLAR is set, the result is left adjusted. If ADLAR is cleared (default), the result is right ad NA $78 io_analo.bmp N ADCL7 ADC Data Register Low Byte Bit 7 RW 0 ADCL6 ADC Data Register Low Byte Bit 6 RW 0 ADCL5 ADC Data Register Low Byte Bit 5 RW 0 ADCL4 ADC Data Register Low Byte Bit 4 RW 0 ADCL3 ADC Data Register Low Byte Bit 3 RW 0 ADCL2 ADC Data Register Low Byte Bit 2 RW 0 ADCL1 ADC Data Register Low Byte Bit 1 RW 0 ADCL0 ADC Data Register Low Byte Bit 0 RW 0 ADCSRB ADC Control and Status Register B NA $7B io_analo.bmp Y ADTS2 ADC Auto Trigger Source 2 If ADATE in ADCSRA is written to one,the value of these bits selects which source will trigger an ADC conversion.If ADATE is cleared,the ADTS2:0 settings will have no effect.A conversion will be triggered by the rising edge of the selected interrupt flag.Note that switching from a trigger source that is cleared to a trigger source that is set,will generate a positive edge on the trigger signal.If ADEN in ADCSRA is set,this will start a conversion.Switching to Free Running Mode (ADTS [2:0 ]=0)will not cause a trigger event,even if the ADC Interrupt Flag is set . RW 0 ADTS1 ADC Auto Trigger Source 1 If ADATE in ADCSRA is written to one,the value of these bits selects which source will trigger an ADC conversion.If ADATE is cleared,the ADTS2:0 settings will have no effect.A conversion will be triggered by the rising edge of the selected interrupt flag.Note that switching from a trigger source that is cleared to a trigger source that is set,will generate a positive edge on the trigger signal.If ADEN in ADCSRA is set,this will start a conversion.Switching to Free Running Mode (ADTS [2:0 ]=0)will not cause a trigger event,even if the ADC Interrupt Flag is set . RW 0 ADTS0 ADC Auto Trigger Source 0 If ADATE in ADCSRA is written to one,the value of these bits selects which source will trigger an ADC conversion.If ADATE is cleared,the ADTS2:0 settings will have no effect.A conversion will be triggered by the rising edge of the selected interrupt flag.Note that switching from a trigger source that is cleared to a trigger source that is set,will generate a positive edge on the trigger signal.If ADEN in ADCSRA is set,this will start a conversion.Switching to Free Running Mode (ADTS [2:0 ]=0)will not cause a trigger event,even if the ADC Interrupt Flag is set . RW 0 DIDR0 Digital Input Disable Register 0 NA $7E io_analo.bmp Y ADC7D ADC7 Digital input Disable When this bit is written logic one,the digital input buffer on the corresponding ADC pin is disabled.The corresponding PIN register bit will always read as zero when this bit is set.When an analog signal is applied to the ADC7..0 pin and the digital input from this pin is not needed,this bit should be written logic one to reduce power consumption in the digital input buffer. ADC6D ADC6 Digital input Disable When this bit is written logic one,the digital input buffer on the corresponding ADC pin is disabled.The corresponding PIN register bit will always read as zero when this bit is set.When an analog signal is applied to the ADC7..0 pin and the digital input from this pin is not needed,this bit should be written logic one to reduce power consumption in the digital input buffer. ADC5D ADC5 Digital input Disable When this bit is written logic one,the digital input buffer on the corresponding ADC pin is disabled.The corresponding PIN register bit will always read as zero when this bit is set.When an analog signal is applied to the ADC7..0 pin and the digital input from this pin is not needed,this bit should be written logic one to reduce power consumption in the digital input buffer. ADC4D ADC4 Digital input Disable When this bit is written logic one,the digital input buffer on the corresponding ADC pin is disabled.The corresponding PIN register bit will always read as zero when this bit is set.When an analog signal is applied to the ADC7..0 pin and the digital input from this pin is not needed,this bit should be written logic one to reduce power consumption in the digital input buffer. ADC3D ADC3 Digital input Disable When this bit is written logic one,the digital input buffer on the corresponding ADC pin is disabled.The corresponding PIN register bit will always read as zero when this bit is set.When an analog signal is applied to the ADC7..0 pin and the digital input from this pin is not needed,this bit should be written logic one to reduce power consumption in the digital input buffer. ADC2D ADC2 Digital input Disable When this bit is written logic one,the digital input buffer on the corresponding ADC pin is disabled.The corresponding PIN register bit will always read as zero when this bit is set.When an analog signal is applied to the ADC7..0 pin and the digital input from this pin is not needed,this bit should be written logic one to reduce power consumption in the digital input buffer. ADC1D ADC1 Digital input Disable When this bit is written logic one,the digital input buffer on the corresponding ADC pin is disabled.The corresponding PIN register bit will always read as zero when this bit is set.When an analog signal is applied to the ADC7..0 pin and the digital input from this pin is not needed,this bit should be written logic one to reduce power consumption in the digital input buffer. ADC0D ADC0 Digital input Disable When this bit is written logic one,the digital input buffer on the corresponding ADC pin is disabled.The corresponding PIN register bit will always read as zero when this bit is set.When an analog signal is applied to the ADC7..0 pin and the digital input from this pin is not needed,this bit should be written logic one to reduce power consumption in the digital input buffer. [SPMCSR] io_cpu.bmp AVRSimIOSPM.SimIOSPM The Boot Loader Support provides a real Read While Write self-programming mechanism for downloading and uploading program code by the MCU itself. This feature allows flexible application software updates controlled by the MCU using a Flash-resident Boot Loader program. The Boot Loader program can use any available data interface and associated proto-col to read code and write (program) that code into the Flash memory, or read the code from the program memory. The program code within the Boot Loader section has the capability to write into the entire Flash, including the Boot Loader Memory. The Boot Loader can thus even modify itself, and it can also erase itself from the code if the feature is not needed anymore. The size of the Boot Loader Memory is configurable with fuses and the Boot Loader has two separate sets of Boot Lock Bits which can be set independently. This gives the user a unique flexibility to select different levels of protection. Boot Loader Features: Read While Write self-programming. Flexibl Boot Memory size. High security (separate Boot Lock bits for a flexible protection). Separate fuse to select reset vector Optimized page (1) size. Code efficient algorithm Efficient read-modify-write suppor SPMCSR SPMCR Store Program Memory Control Register The Store Program Memory Control Register contains the control bits needed to control the Boot Loader operations. $37 $57 io_flag.bmp Y SPMIE SPM Interrupt Enable When the SPMIE bit is written to one, and the I-bit in the Status Register is set (one), the SPM ready interrupt will be enabled. The SPM ready Interrupt will be executed as long as the SPMEN bit in the SPMCR register is cleared. RW 0 RWWSB ASB Read While Write Section Busy When a self-programming (page erase or page write) operation to the RWW section is initiated, the RWWSB will be set (one) by hardware. When the RWWSB bit is set, the RWW section cannot be accessed. The RWWSB bit will be cleared if the RWWSRE bit is written to one after a self-programming operation is completed. Alternatively the RWWSB bit will auto-matically be cleared if a page load operation is initiated. R 0 RWWSRE ASRE Read While Write section read enable When programming (page erase or page write) to the RWW section, the RWW section is blocked for reading (the RWWSB will be set by hardware). To re-enable the RWW section, the user software must wait until the programming is completed (SPMEN will be cleared). Then, if the RWWSRE bit is written to one at the same time as SPMEN, the next SPM instruction within four clock cycles re-enables the RWW section. The RWW section cannot be re-enabled while Flash is busy with a page erase or a page write (SPMEN is set). If the RWWSRE bit is written while the Flash is being loaded, the Flash load operation will abort and the data loaded will be lo RW 0 BLBSET Boot Lock Bit Set If this bit is written to one at the same time as SPMEN, the next SPM instruction within four clock cycles sets Boot Lock bits, according to the data in R0. The data in R1 and the address in the Z pointer are ignored. The BLBSET bit will automatically be cleared upon completion of the lock bit set, or if no SPM instruction is executed within four clock cycles. An LPM instruction within three cycles after BLBSET and SPMEN are set in the SPMCR register, will read either the Lock-bits or the Fuse bits (depending on Z0 in the Z pointer) into the destination register. See “Reading the Fuse and Lock Bits from Software” on page 235 for details RW 0 PGWRT Page Write If this bit is written to one at the same time as SPMEN, the next SPM instruction within four clock cycles executes page write, with the data stored in the temporary buffer. The page address is taken from the high part of the Z pointer. The data in R1 and R0 are ignored. The PGWRT bit will auto-clear upon completion of a page write, or if no SPM instruction is exe-cuted within four clock cycles. The CPU is halted during the entire page write operation if the NRWW section is addressed. RW 0 PGERS Page Erase If this bit is written to one at the same time as SPMEN, the next SPM instruction within four clock cycles executes page erase. The page address is taken from the high part of the Z pointer. The data in R1 and R0 are ignored. The PGERS bit will auto-clear upon completion of a page erase, or if no SPM instruction is executed within four clock cycles. The CPU is halted during the entire page write operation if the NRWW section is addressed. RW 0 SPMEN Store Program Memory Enable This bit enables the SPM instruction for the next four clock cycles. If written to one together with either RWWSRE, BLB-SET, PGWRT or PGERS, the following SPM instruction will have a special meaning, see description above. If only SPMEN is written, the following SPM instruction will store the value in R1:R0 in the temporary page buffer addressed by the Z pointer. The LSB of the Z pointer is ignored. The SPMEN bit will auto-clear upon completion of an SPM instruction, or if no SPM instruction is executed within four clock cycles. During page erase and page write, the SPMEN bit remain high until the operation is completed. Writing any other combination than “10001”, "01001", "00101", "00011" or "00001" in the lower five bits will have no effec RW 0 [UDR0:UCSR0A:UCSR0B:UCSR0C:UBRR0H:UBRR0L] [UBRR0H:UBRR0L] io_com.bmp The Universal Synchronous and Asynchronous serial Receiver and Transmitter (USART) is a highly flexible serial communication device. The main features are: • Full Duplex Operation (Independent Serial Receive and Transmit Registers) • Asynchronous or Synchronous Operation • Master or Slave Clocked Synchronous Operation • High Resolution Baud Rate Generator • Supports Serial Frames with 5, 6, 7, 8 or 9 Data Bits and 1 or 2 Stop Bits • Odd or Even Parity Generation and Parity Check Supported by Hardware • Data OverRun Detection • Framing Error Detection • Noise Filtering Includes False Start Bit Detection and Digital Low Pass Filter • Three Separate Interrupts on TX Complete, TX Data Register Empty and RX Complete • Multi-processor Communication Mode • Double Speed Asynchronous Communica UDR0 UDR USART I/O Data Register The UDR0 register is actually two physically separate registers sharing the same I/O address. When writing to the register, the USART Transmit Data register is written. When reading from UDR0, the USART Receive Data register is read. NA $C6 io_com.bmp N UDR07 USART I/O Data Register bit 7 RW 0 UDR06 USART I/O Data Register bit 6 RW 0 UDR05 USART I/O Data Register bit 5 RW 0 UDR04 USART I/O Data Register bit 4 RW 0 UDR03 USART I/O Data Register bit 3 RW 0 UDR02 USART I/O Data Register bit 2 RW 0 UDR01 USART I/O Data Register bit 1 RW 0 UDR00 USART I/O Data Register bit 0 RW 0 UCSR0A UCSRA USR USART Control and Status Register A NA $C0 io_flag.bmp Y RXC0 RXC USART Receive Complete This bit is set (one) when a received character is transferred from the Receiver Shift register to UDR0. The bit is set regard-less of any detected framing errors. When the RXCIE bit in UCR is set, the USART Receive Complete interrupt will be executed when RXC is set(one). RXC is cleared by reading UDR0. When interrupt-driven data reception is used, the USART Receive Complete Interrupt routine must read UDRin order to clear RXC, otherwise a new interrupt will occur once the interrupt routine terminates. R 0 TXC0 TXC USART Transmit Complete This bit is set (one) when the entire character (including the stop bit) in the Transmit Shift register has been shifted out and no new data has been written to UDR0. This flag is especially useful in half-duplex communications interfaces, where a transmitting application must enter receive mode and free the communications bus immediately after completing the transmission. When the TXCIE bit in UCR is set, setting of TXC causes the USART Transmit Complete interrupt to be executed. TXC is cleared by hardware when executing the corresponding interrupt handling vector. Alternatively, the TXC bit is cleared (zero) by writing a logical one to the b RW 0 UDRE0 UDRE USART Data Register Empty This bit is set (one) when a character written to UDRis transferred to the Transmit shift register. Setting of this bit indicates that the transmitter is ready to receive a new character for transmission. When the UDR0IE bit in UCR is set, the USART Transmit Complete interrupt to be executed as long as UDR0E is set. UDR0E is cleared by writing UDR0. When interrupt-driven data transmittal is used, the USART Data Register Empty Interrupt routine must write UDRin order to clear UDR0E, otherwise a new interrupt will occur once the interrupt routine terminates. UDR0E is set (one) during reset to indicate that the transmitter is r R 1 FE0 FE Framing Error This bit is set if a Framing Error condition is detected, i.e. when the stop bit of an incoming character is zero. The FE bit is cleared when the stop bit of received data is one. R 0 DOR0 DOR Data OverRun This bit is set if an Overrun condition is detected, i.e. when a character already present in the UDRregister is not read before the next character has been shifted into the Receiver Shift register. The OR bit is buffered, which means that it will be set once the valid data still in UDR0E is read. The OR bit is cleared (zero) when data is received and transferred to UDR0. R 0 UPE0 UPE USART Parity Error This bit is set if the next character in the receive buffer had a Parity Error when received and the parity checking was enabled at that point (UPM1 = 1). This bit is valid until the receive buffer (UDR0) is read. Always set this bit to zero when writing to UCSR0A. R 0 U2X0 U2X Double the USART Transmission Speed This bit only has effect for the asynchronous operation. Write this bit to zero when using synchronous operation. Writing this bit to one will reduce the divisor of the baud rate divider from 16 to 8 effectively doubling the transfer rate for asynchronous communication. RW 0 MPCM0 MPCM Multi-processor Communication Mode This bit enables the Multi-processor Communication Mode. When the MPCM bit is written to one, all the incoming frames received by the USART receiver that do not contain address information will be ignored. The transmitter is unaffected by the MPCM setting. For more detailed information see “Multi-processor Communication Mode” on page 152. RW 0 UCSR0B UCSRB UCR USART Control and Status Register B NA $C1 io_flag.bmp Y RXCIE0 RXCIE RX Complete Interrupt Enable Writing this bit to one enables interrupt on the RXC flag. A USART Receive Complete interrupt will be generated only if the RXCIE bit is written to one, the global interrupt flag in SREG is written to one and the RXC bit in UCSR0A is set. RW 0 TXCIE0 TXCIE TX Complete Interrupt Enable Writing this bit to one enables interrupt on the TXC flag. A USART Transmit Complete interrupt will be generated only if the TXCIE bit is written to one, the global interrupt flag in SREG is written to one and the TXC bit in UCSR0A is set. RW 0 UDRIE0 UDRIE USART Data Register Empty Interrupt Enable Writing this bit to one enables interrupt on the UDR0E flag. A Data Register Empty interrupt will be generated only if the UDR0IE bit is written to one, the global interrupt flag in SREG is written to one and the UDR0E bit in UCSR0A is set. RW 1 RXEN0 RXEN Receiver Enable Writing this bit to one enables the USART receiver. The receiver will override normal port operation for the RxD pin when enabled. Disabling the receiver will flush the receive buffer invalidating the FE, DOR and PE flags. RW 0 TXEN0 TXEN Transmitter Enable Writing this bit to one enables the USART transmitter. The transmitter will override normal port operation for the TxD pin when enabled. The disabling of the transmitter (writing TXEN to zero) will not become effective until ongoing and pending transmissions are completed, i.e. when the transmit shift register and transmit buffer register does not contain data to be transmitted. When disabled, the transmitter will no longer override the TxD port. RW 0 UCSZ02 UCSZ2 Character Size The UCSZ2 bits combined with the UCSZ1:0 bit in UCSR0C sets the number of data bits (character size) in a frame the receiver and transmitter use. RW 0 RXB80 RXB8 Receive Data Bit 8 RXB8 is the 9th data bit of the received character when operating with serial frames with 9 data bits. Must be read before reading the low bits from UDR0. R 0 TXB80 TXB8 Transmit Data Bit 8 TXB8 is the 9th data bit in the character to be transmitted when operating with serial frames with 9 data bits. Must be writ-ten before writing the low bits to UDR0. W 0 UCSR0C UCSRC USART Control and Status Register C NA $C2 io_flag.bmp Y UMSEL0 UMSEL USART Mode Select 0: Asynchronous Operation. 1: Synchronous Operation RW 0 UPM01 UPM1 Parity Mode Bit 1 This bit enable and set type of parity generation and check. If enabled, the transmitter will automatically generate and send the parity of the transmitted data bits within each frame. The receiver will generate a parity value for the incoming data and compare it to the UPM0 setting. If a mismatch is detected, the PE flag in UCSR0A will be set. RW 0 UPM00 UPM0 Parity Mode Bit 0 This bit enable and set type of parity generation and check. If enabled, the transmitter will automatically generate and send the parity of the transmitted data bits within each frame. The receiver will generate a parity value for the incoming data and compare it to the UPM0 setting. If a mismatch is detected, the PE flag in UCSR0A will be set. RW 0 USBS0 USBS Stop Bit Select 0: 1-bit. 1: 2-bit. RW 0 UCSZ01 UCSZ1 Character Size Character Size: 0 0 0 = 5-bit. 0 0 1 = 6-bit. 0 1 0 = 7 bit. 0 1 1 = 8-bit. 1 1 1 = 9 bit. RW 0 UCSZ00 UCSZ0 Character Size Character Size: 0 0 0 = 5-bit. 0 0 1 = 6-bit. 0 1 0 = 7 bit. 0 1 1 = 8-bit. 1 1 1 = 9 bit. RW 1 UCPOL0 UCPOL Clock Polarity This bit is used for synchronous mode only. Write this bit to zero when asynchronous mode is used. The UCPOL bit sets the relationship between data output change and data input sample, and the synchronous clock (XCK). RW 0 UBRR0H UBRRH USART Baud Rate Register High Byte This is a 12-bit register which contains the USART baud rate. The UBRR0H contains the 4 most significant bits, and the UBRR0L contains the 8 least significant bits of the USART baud rate. Ongoing transmissions by the transmitter and receiver will be corrupted if the baud rate is changed. Writing UBRR0L will trigger an immediate update of the baud rate prescaler. NA $C5 io_com.bmp N UBRR11 USART Baud Rate Register bit 11 RW 0 UBRR10 USART Baud Rate Register bit 10 RW 0 UBRR9 USART Baud Rate Register bit 9 RW 0 UBRR8 USART Baud Rate Register bit 8 RW 0 UBRR0L UBRRL UBRR0 UBRR USART Baud Rate Register Low Byte This is a 12-bit register which contains the USART baud rate. The UBRR0H contains the 4 most significant bits, and the UBRR0L contains the 8 least significant bits of the USART baud rate. Ongoing transmissions by the transmitter and receiver will be corrupted if the baud rate is changed. Writing UBRR0L will trigger an immediate update of the baud rate prescaler. NA $C4 io_com.bmp N UBRR7 USART Baud Rate Register bit 7 RW 0 UBRR6 USART Baud Rate Register bit 6 RW 0 UBRR5 USART Baud Rate Register bit 5 RW 0 UBRR4 USART Baud Rate Register bit 4 RW 0 UBRR3 USART Baud Rate Register bit 3 RW 0 UBRR2 USART Baud Rate Register bit 2 RW 0 UBRR1 USART Baud Rate Register bit 1 RW 0 UBRR0 USART Baud Rate Register bit 0 RW 0 [LCDCRA:LCDCRB:LCDFRR:LCDCCR:LCDDR18:LCDDR17:LCDDR16:LCDDR15:LCDDR13:LCDDR12:LCDDR11:LCDDR10:LCDDR8:LCDDR7:LCDDR6:LCDDR5:LCDDR3:LCDDR2:LCDDR1:LCDDR0] io_cpu.bmp LCDDR18 LCD Data Register 18 NA $FE io_flag.bmp N SEG324 RW 0 LCDDR17 LCD Data Register 17 NA $FD io_flag.bmp N SEG323 RW 0 SEG322 RW 0 SEG321 RW 0 SEG320 RW 0 SEG319 RW 0 SEG318 RW 0 SEG317 RW 0 SEG316 RW 0 LCDDR16 LCD Data Register 16 NA $FC io_flag.bmp N SEG315 RW 0 SEG314 RW 0 SEG313 RW 0 SEG312 RW 0 SEG311 RW 0 SEG310 RW 0 SEG309 RW 0 SEG308 RW 0 LCDDR15 LCD Data Register 15 NA $FB io_flag.bmp N SEG307 RW 0 SEG306 RW 0 SEG305 RW 0 SEG304 RW 0 SEG303 RW 0 SEG302 RW 0 SEG301 RW 0 SEG300 RW 0 LCDDR13 LCD Data Register 13 NA $F9 io_flag.bmp N SEG224 RW 0 LCDDR12 LCD Data Register 12 NA $F8 io_flag.bmp N SEG223 RW 0 SEG222 RW 0 SEG221 RW 0 SEG220 RW 0 SEG219 RW 0 SEG218 RW 0 SEG217 RW 0 SEG216 RW 0 LCDDR11 LCD Data Register 11 NA $F7 io_flag.bmp N SEG215 RW 0 SEG214 RW 0 SEG213 RW 0 SEG212 RW 0 SEG211 RW 0 SEG210 RW 0 SEG209 RW 0 SEG208 RW 0 LCDDR10 LCD Data Register 10 NA $F6 io_flag.bmp N SEG207 RW 0 SEG206 RW 0 SEG205 RW 0 SEG204 RW 0 SEG203 RW 0 SEG202 RW 0 SEG201 RW 0 SEG200 RW 0 LCDDR8 LCD Data Register 8 NA $F4 io_flag.bmp N SEG124 RW 0 LCDDR7 LCD Data Register 7 NA $F3 io_flag.bmp N SEG123 RW 0 SEG122 RW 0 SEG121 RW 0 SEG120 RW 0 SEG119 RW 0 SEG118 RW 0 SEG117 RW 0 SEG116 RW 0 LCDDR6 LCD Data Register 6 NA $F2 io_flag.bmp N SEG115 RW 0 SEG114 RW 0 SEG113 RW 0 SEG112 RW 0 SEG111 RW 0 SEG110 RW 0 SEG109 RW 0 SEG108 RW 0 LCDDR5 LCD Data Register 5 NA $F1 io_flag.bmp N SEG107 RW 0 SEG106 RW 0 SEG105 RW 0 SEG104 RW 0 SEG103 RW 0 SEG102 RW 0 SEG101 RW 0 SEG100 RW 0 LCDDR3 LCD Data Register 3 NA $EF io_flag.bmp N SEG024 RW 0 LCDDR2 LCD Data Register 2 NA $EE io_flag.bmp N SEG023 RW 0 SEG022 RW 0 SEG021 RW 0 SEG020 RW 0 SEG019 RW 0 SEG018 RW 0 SEG017 RW 0 SEG016 RW 0 LCDDR1 LCD Data Register 1 NA $ED io_flag.bmp N SEG015 RW 0 SEG014 RW 0 SEG013 RW 0 SEG012 RW 0 SEG011 RW 0 SEG010 RW 0 SEG009 RW 0 SEG008 RW 0 LCDDR0 LCD Data Register 0 NA $EC io_flag.bmp N SEG007 RW 0 SEG006 RW 0 SEG005 RW 0 SEG004 RW 0 SEG003 RW 0 SEG002 RW 0 SEG001 RW 0 SEG000 RW 0 LCDCCR LCD Contrast Control Register NA $E7 io_flag.bmp Y LCDDC2 RW 0 LCDDC1 RW 0 LCDDC0 RW 0 LCDMDT LCD Maximum Drive Time Writing this bit to one turns the LCD drivers on 100% all the time, regardless og LCDDC2:0 setting R 0 LCDCC3 LCD Contrast Control 3 TheLCDCC3:0bitsdeterminethemaximumvoltageV3onsegmentandcommonpins. RW 0 LCDCC2 LCD Contrast Control 2 TheLCDCC3:0bitsdeterminethemaximumvoltageV3onsegmentandcommonpins. RW 0 LCDCC1 LCD Contrast Control 1 TheLCDCC3:0bitsdeterminethemaximumvoltageV3onsegmentandcommonpins. RW 0 LCDCC0 LCD Contrast Control 0 TheLCDCC3:0bitsdeterminethemaximumvoltageV3onsegmentandcommonpins. RW 0 LCDFRR LCD Frame Rate Register NA $E6 io_flag.bmp Y LCDPS2 LCD Prescaler Select 2 The LCDPS2:0 bits determine the prescaler value.The base clock can be further divided by setting the base clock divide bits 2:0. RW 0 LCDPS1 LCD Prescaler Select 1 The LCDPS2:0 bits determine the prescaler value.The base clock can be further divided by setting the base clock divide bits 2:0. RW 0 LCDPS0 LCD Prescaler Select 0 The LCDPS2:0 bits determine the prescaler value.The base clock can be further divided by setting the base clock divide bits 2:0. RW 0 LCDCD2 LCD Clock Divider 2 The LCDCD2:0 bits determine the base-clock division ratio. RW 0 LCDCD1 LCD Clock Divider 1 The LCDCD2:0 bits determine the base-clock division ratio. RW 0 LCDCD0 LCD Clock Divider 0 The LCDCD2:0 bits determine the base-clock division ratio. RW 0 LCDCRB LCD Control and Status Register B NA $E5 io_flag.bmp Y LCDCS LCD CLock Select When this bit is written to zero,the chip clock is used.When this bit is written to one,the 32 kHz timer oscillator clock is used. RW 0 LCD2B LCD 1/2 Bias Select When this bit is written to zero,1/3 bias is used.When this bit is written to one,1/2 bias is used RW 0 LCDMUX1 LCD Mux Select 1 The LCDMUX1:0 bits determine the duty cycle.Common pins that are not used my be used as ordinary port pins. RW 0 LCDMUX0 LCD Mux Select 0 The LCDMUX1:0 bits determine the duty cycle.Common pins that are not used my be used as ordinary port pins. RW 0 LCDPM3 LCD Port Mask 3 The LCDPM3:0 bits determine the number of port pin to be used as segment driver. RW 0 LCDPM2 LCD Port Mask 2 The LCDPM2:0 bits determine the number of port pin to be used as segment driver. RW 0 LCDPM1 LCD Port Mask 1 The LCDPM2:0 bits determine the number of port pin to be used as segment driver. RW 0 LCDPM0 LCD Port Mask 0 The LCDPM2:0 bits determine the number of port pin to be used as segment driver. RW 0 LCDCRA LCD Control Register A NA $E4 io_flag.bmp Y LCDEN LCD Enable Writing this bit to one enables the LCD.By writing it to zero,the LCD is turned off.Turning the LCD off while driving a display,enables ordinary port function,and DC will then be applied to the display if ports are configured as output. RW 0 LCDAB LCD A or B waveform When LCDAB is written logic zero,waveform A is output on port pins.When LCDAB is written logic one,waveform B is output on port pins.If this bit is modified during display operation the change takes place in the beginning of a newframe. RW 0 LCDIF LCD Interrupt Flag This bit is set by hardware at the beginning of a new frame,at the same time as the display data is updated.The LCD Frame Complete Interrupt is executed if the LCDIE bit and the I-bit in SREG are set.LCDIF is cleared by hardware when executing the corresponding interrupt handling vector.Alternatively,LCDIF is cleared by writing a logical one to the flag. RW 0 LCDIE LCD Interrupt Enable When this bit is written to one and the I-bit in SREG is set,the LCD Frame Complete Interrupt is enabled. RW 0 LCDBD LCD Buffer Disable Write this to one to decrease power consumption R 0 LCDCCD LCD Contrast Control Disable Write this to one to disable the internal LCD power supply. R 0 LCDBL LCD Blanking When this bit is written to one,the display will be blanked after completion of a frame.All segment and common pins will be driven to ground. RW 0 [SREG:SPH:SPL:MCUCR:MCUSR:OSCCAL:CLKPR:PRR:SMCR:GPIOR2:GPIOR1:GPIOR0] [SPH:SPL] io_cpu.bmp SREG Status Register $3F $5F io_sreg.bmp Y I Global Interrupt Enable The global interrupt enable bit must be set (one) for the interrupts to be enabled. The individual interrupt enable control is then performed in separate control registers. If the global interrupt enable bit is cleared (zero), none of the interrupts are enabled independent of the individual interrupt enable settings. The I-bit is cleared by hardware after an interrupt has occurred, and is set by the RETI instruction to enable subsequent interrupts. RW 0 T Bit Copy Storage The bit copy instructions BLD (Bit LoaD) and BST (Bit STore) use the T bit as source and destination for the operated bit. A bit from a register in the register file can be copied into T by the BST instruction, and a bit in T can be copied into a bit in a register in the register file by the BLD instruction. RW 0 H Half Carry Flag The half carry flag H indicates a half carry in some arithmetic operations. See the Instruction Set Description for detailed information. RW 0 S Sign Bit The S-bit is always an exclusive or between the negative flag N and the two’s complement overflow flag V. See the Instruc-tion Set Description for detailed information. RW 0 V Two's Complement Overflow Flag The two’s complement overflow flag V supports two’s complement arithmetics. See the Instruction Set Description for detailed information. RW 0 N Negative Flag The negative flag N indicates a negative result after the different arithmetic and logic operations. See the Instruction Set Description for detailed information. RW 0 Z Zero Flag The zero flag Z indicates a zero result after the different arithmetic and logic operations. See the Instruction Set Description for detailed information. RW 0 C Carry Flag The carry flag C indicates a carry in an arithmetic or logic operation. See the Instruction Set Description for detailed information. Note that the status register is not automatically stored when entering an interrupt routine and restored when returning from an interrupt routine. This must be handled by software. RW 0 SPH Stack Pointer High The general AVR 16-bit Stack Pointer is effectively built up of two 8-bit registers in the I/O space locations $3E ($5E) and $3D ($5D). As the AT90S4414/8515 supports up to 64 kB external SRAM, all 16-bits are used. The Stack Pointer points to the data SRAM stack area where the Subroutine and Interrupt Stacks are located. This Stack space in the data SRAM must be defined by the program before any subroutine calls are executed or interrupts are enabled. The stack pointer must be set to point above $60. The Stack Pointer is decremented by one when data is pushed onto the Stack with the PUSH instruction, and it is decremented by two when an address is pushed onto the Stack with subroutine calls and interrupts. The Stack Pointer is incremented by one when data is popped from the Stack with the POP instruction, and it is incremented by two when an address is popped from the Stack with return from subroutine RET or return from interrupt R $3E $5E io_sph.bmp N SP15 Stack pointer bit 15 RW 0 SP14 Stack pointer bit 14 RW 0 SP13 Stack pointer bit 13 RW 0 SP12 Stack pointer bit 12 RW 0 SP11 Stack pointer bit 11 RW 0 SP10 Stack pointer bit 10 RW 0 SP9 Stack pointer bit 9 RW 0 SP8 Stack pointer bit 8 RW 0 SPL Stack Pointer Low The general AVR 16-bit Stack Pointer is effectively built up of two 8-bit registers in the I/O space locations $3E ($5E) and $3D ($5D). As the AT90S4414/8515 supports up to 64 kB external SRAM, all 16-bits are used. The Stack Pointer points to the data SRAM stack area where the Subroutine and Interrupt Stacks are located. This Stack space in the data SRAM must be defined by the program before any subroutine calls are executed or interrupts are enabled. The stack pointer must be set to point above $60. The Stack Pointer is decremented by one when data is pushed onto the Stack with the PUSH instruction, and it is decremented by two when an address is pushed onto the Stack with subroutine calls and interrupts. The Stack Pointer is incremented by one when data is popped from the Stack with the POP instruction, and it is incremented by two when an address is popped from the Stack with return from subroutine RET or return from interrupt $3D $5D io_sph.bmp N SP7 Stack pointer bit 7 RW 0 SP6 Stack pointer bit 6 RW 0 SP5 Stack pointer bit 5 RW 0 SP4 Stack pointer bit 4 RW 0 SP3 Stack pointer bit 3 RW 0 SP2 Stack pointer bit 2 RW 0 SP1 Stack pointer bit 1 RW 0 SP0 Stack pointer bit 0 RW 0 MCUCR MCU Control Register The MCU Control Register contains control bits for general MCU functions. $35 $55 io_flag.bmp Y JTD JTAG Interface Disable Write to zero to enable the JTAG interface if the JTAGEN fuse is programmed RW 0 BODS BOD Sleep Write to one in order to turn off BOD during sleep R 0 BODSE BOD Sleep Enable BODSE enables setting of BODS control bit R 0 PUD Pull-up disable When this bit is written to one,the pull-ups in the I/O ports are disabled even if the DDxn and PORTxn registers are configured to enable the pull-ups ({DDxn,PORTxn}=0b01). RW 0 IVSEL Interrupt Vector Select When the IVSEL bit is cleared (zero),the interrupt vectors are placed at the start of the Flash memory.When this bit is set (one),the interrupt vectors are moved to the beginning of the Boot Loader section of the flash.The actual address of the start of the boot flash section is determined by the BOOTSZ fuses. RW 0 IVCE Interrupt Vector Change Enable The IVCE bit must be written to logic one to enable change of the IVSEL bit.IVCE is cleared by hardware four cycles after it is written or when IVSEL is written.Setting the IVCE bit will disable interrupts. RW 0 MCUSR MCU Status Register The MCU Status Register provides information on which reset source caused an MCU reset. To make use of the reset flags to identify a reset condition, the user should read and then reset the MCUCSR as early as possible in the program. If the register is cleared before another reset occurs, the source of the reset can be found by examining the reset flags. $34 $54 io_flag.bmp Y JTRF JTAG Reset Flag This bit is set if a reset is being caused by a logic one in the JTAG Reset Register selected by the JTAG instruction AVR_RESET. This bit is reset by a Power-on reset, or by writing a logic zero to the flag. R/W 0 WDRF Watchdog Reset Flag This bit is set if a watchdog reset occurs. The bit is reset by a power-on reset, or by writing a logic zero to the flag. R/W 0 BORF Brown-out Reset Flag This bit is set if a brown-out reset occurs. The bit is reset by a power-on reset, or by writing a logic zero to the flag. R/W 0 EXTRF External Reset Flag This bit is set if an external reset occurs. The bit is reset by a power-on reset, or by writing a logic zero to the flag. R/W 0 PORF Power-on reset flag This bit is set if a power-on reset occurs. The bit is reset only by writing a logic zero to the flag. R/W 0 OSCCAL Oscillator Calibration Value Writing the calibration byte to this address will trim the internal oscillator to remove process variations from the oscillator frequency. This is done automatically during chip reset. When OSCCAL is zero, the lowest available frequency is chosen. Writing non-zero values to this register will increase the frequency of the internal oscillator. Writing $FF to the register gives the highest available frequency. The calibrated oscillator is used to time EEPROM and Flash access. If EEPROM or Flash is written, do not calibrate to more than 10% above the nominal frequency. Otherwise, the EEPROM or Flash write may fail. Note that the Oscillator is intended for calibration to 1.0 MHz, 2.0 MHz, 4.0 MHz, or 8.0MHz. Tuning to other values is not guaranteed, as indicated in Table 14 NA $66 io_cpu.bmp N CAL7 Oscillator Calibration Value Bit7 R/W 0 CAL6 Oscillator Calibration Value Bit6 R/W 0 CAL5 Oscillator Calibration Value Bit5 R/W 0 CAL4 Oscillator Calibration Value Bit4 R/W 0 CAL3 Oscillator Calibration Value Bit3 R/W 0 CAL2 Oscillator Calibration Value Bit2 R/W 0 CAL1 Oscillator Calibration Value Bit1 R/W 0 CAL0 Oscillator Calibration Value Bit0 R/W 0 CLKPR Clock Prescale Register NA $61 io_cpu.bmp Y CLKPCE Clock Prescaler Change Enable The CLKPCE bit must be written to logic one to enable change of the CLKPS bits. The CLKPCE bit is only updated when the other bits in CLKPR are simultaneously written to zero. CLKPCE is cleared by hardware four cycles after it is written or when CLKPS bits are written. Rewriting the CLKPCE bit within this time-out period does neither extend the time-out period, nor clear the CLKPCE bit. RW 0 CLKPS3 Clock Prescaler Select Bit 3 RW 0 CLKPS2 Clock Prescaler Select Bit 2 RW 0 CLKPS1 Clock Prescaler Select Bit 1 RW 0 CLKPS0 Clock Prescaler Select Bit 0 RW 0 PRR Power Reduction Register The Power Reduction Register, PRR, provides a method to stop the clock to individual peripherals to reduce power consumption. NA $64 io_cpu.bmp Y PRLCD Power Reduction LCD Writing logic one to this bit shuts down the LCD controller. The LCD controller must be disabled and the display discharged before shut down. R/W 0 PRTIM1 Power Reduction Timer/Counter1 Writing logic one to this bit shuts down the Timer/Counter1 module. When Timer/Counter1 is enabled, operation will continue like before the shutdown. R/W 0 PRSPI Power Reduction Serial Peripheral Interface Writing logic one to this bit shuts down the Serial Peripheral Interface by stopping the clock to the module. When waking up the SPI again, the SPI should be reinitialised to ensure proper operation. R/W 0 PRUSART0 Power Reduction USART Writing logic one to this bit shuts down the USART by stopping the clock to the module. When waking up the USART again, the USART should be reinitialised to ensure proper operation. R/W 0 PRADC Power Reduction ADC Writing logic one to this bit shuts down the ADC. The ADC must be disabled before shut down. The analog comparator cannot use the ADC input MUX when the ADC is shut down. R/W 0 SMCR Sleep Mode Control Register The Sleep Mode Control Register contains control bits for power management. $33 $53 io_cpu.bmp Y SM2 Sleep Mode Select bit 2 These bits select between the five available sleep modes. RW 0 SM1 Sleep Mode Select bit 1 These bits select between the five available sleep modes. RW 0 SM0 Sleep Mode Select bit 0 These bits select between the five available sleep modes. RW 0 SE Sleep Enable The SE bit must be written to logic one to make the MCU enter the sleep mode when the SLEEP instruction is executed.To RW 0 GPIOR2 General Purpose IO Register 2 The General Purpose I/O Registers can be used for storing any information, and they are particularly useful for storing global variables and status flags. General Purpose I/O Registers within the address range 0x00 - 0x1F are directly bit-accessible using the SBI, CBI, SBIS, and SBIC instructions. $2B $4B io_cpu.bmp N GPIOR27 General Purpose IO Register 2 bit 7 RW 0 GPIOR26 General Purpose IO Register 2 bit 6 RW 0 GPIOR25 General Purpose IO Register 2 bit 5 RW 0 GPIOR24 General Purpose IO Register 2 bit 4 RW 0 GPIOR23 General Purpose IO Register 2 bit 3 RW 0 GPIOR22 General Purpose IO Register 2 bit 2 RW 0 GPIOR21 General Purpose IO Register 2 bit 1 RW 0 GPIOR20 General Purpose IO Register 2 bit 0 RW 0 GPIOR1 General Purpose IO Register 1 The General Purpose I/O Registers can be used for storing any information, and they are particularly useful for storing global variables and status flags. General Purpose I/O Registers within the address range 0x00 - 0x1F are directly bit-accessible using the SBI, CBI, SBIS, and SBIC instructions. $2A $4A io_cpu.bmp N GPIOR17 General Purpose IO Register 1 bit 7 RW 0 GPIOR16 General Purpose IO Register 1 bit 6 RW 0 GPIOR15 General Purpose IO Register 1 bit 5 RW 0 GPIOR14 General Purpose IO Register 1 bit 4 RW 0 GPIOR13 General Purpose IO Register 1 bit 3 RW 0 GPIOR12 General Purpose IO Register 1 bit 2 RW 0 GPIOR11 General Purpose IO Register 1 bit 1 RW 0 GPIOR10 General Purpose IO Register 1 bit 0 RW 0 GPIOR0 General Purpose IO Register 0 The General Purpose I/O Registers can be used for storing any information, and they are particularly useful for storing global variables and status flags. General Purpose I/O Registers within the address range 0x00 - 0x1F are directly bit-accessible using the SBI, CBI, SBIS, and SBIC instructions. $1E $3E io_cpu.bmp N GPIOR07 General Purpose IO Register 0 bit 7 RW 0 GPIOR06 General Purpose IO Register 0 bit 6 RW 0 GPIOR05 General Purpose IO Register 0 bit 5 RW 0 GPIOR04 General Purpose IO Register 0 bit 4 RW 0 GPIOR03 General Purpose IO Register 0 bit 3 RW 0 GPIOR02 General Purpose IO Register 0 bit 2 RW 0 GPIOR01 General Purpose IO Register 0 bit 1 RW 0 GPIOR00 General Purpose IO Register 0 bit 0 RW 0 [STK500:STK500_2:AVRISPmkII:JTAGICEmkII:AVRDragon:ICE50:SIMULATOR] 0x94 1 1 1 0xFF 0xFF 0xFF 0 1 2001002532030x53114510x41128100x400x4C0x000x000x000x414100xC10xC20x000x000x0025625644440x0E 0x1E 0x0F 0x1F 0x2E 0x3E 0x2F 0x3F 0x4E 0x5E 0x4F 0x5F 0x6E 0x7E 0x6F 0x7F 0x66 0x76 0x67 0x77 0x6A 0x7A 0x6B 0x7B 0xBE 0xFD 0x00 0x01 0x00 0x00 0x00 0x001000511510151501050x0F25625650x052562560505 0x0950B03F JTAG 0xFF,0xFF,0xFF,0xF0,0xDF,0x3C,0xB9,0xE0 0xB6,0x6D,0x1B,0xE0,0xDF,0x1C,0xB8,0xE0 0X00,0X00,0X00,0X00,0X00,0X00,0X00,0X00 0X00,0X00,0X00,0X00,0X00,0X00,0X00,0X00 0x53,0xDA,0x01,0xDF,0xF7,0x0F,0x00,0x00,0x00,0x00,0x4D,0x07,0x37,0x00,0x00,0x00,0xF0,0xF0,0xDE,0x7B 0x53,0xDA,0x01,0xD8,0xF7,0x0F,0x00,0x00,0x00,0x00,0x4D,0x05,0x36,0x00,0x00,0x00,0xE0,0xF0,0xDE,0x7B 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 0x31 0X57 0X00 128 4 0x3F00 0x3F00 0x3E00 0x3C00 0x3800 0xFE 0x8000 0x0000,32 0x0020,64 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x3e 0x3d 0x00 0x40 0x00 0x00 0x00 0x01 0x40 0x3f 0x05 0x0F 0x0F 0x0F 0x05 0x05 0x05 0x05 0x05 0x05 0x05 0x05 0x05 0x0F 0x0F 0x0F 0x15 0x14 0x14 0x000008FF 0x00000000 0x00000000 0x00000000 0x000003FF 0x00007FFF 0x00003FFF 0x00003FFF 0x00003FFF 0x00003FFF 0x000008FF 0x0000FFFF 0x000003FF 0x00000000 0x00000000 0x00000000 0x0023FFFF 0x00000FFF 0x000000FF 0xF9 0xff 0x62 0xff 0x66 0xC7 ATmega329.bin 0x02 0x00 1000000 40000000 7 2 ; INTOSC = 1, INTRC=2;EXTCLK=4 1 ;NOTUSE = 1, EXTERNAL = 4, INTERNAL = 2 1 0 0xA0 0xA0 8 0x00000600 0x00000600 Boot Size 256 Words, 4 pages, $3F00-$3FFF, Boot reset $3F00 0x00000600 0x00000400 Boot Size 512 Words, 8 pages, $3E00-$3FFF, Boot reset $3E00 0x00000600 0x00000200 Boot Size 1024 Words, 16 pages, $3C00-$3FFF, Boot reset $3C00 0x00000600 0x00000000 Boot Size 2048 Words, 32 pages, $3800-$3FFF, Boot reset $3800 0x00000031 0x00000000 258 CK, 4 ms 0x00000031 0x00000010 258 CK, 64 ms 0x00000031 0x00000020 1K CK 0x00000031 0x00000030 1K CK, 4 ms 0x00000031 0x00000001 1K CK, 64 ms 0x00000031 0x00000011 16K CK 0x00000031 0x00000021 16K CK, 4 ms 0x00000031 0x00000031 16K CK, 64 ms 0x00000030 0x00000000 6 CK,14 CK 0x00000030 0x00000010 6 CK, 14 CK + 4.1ms 0x00000030 0x00000020 6 CK, 65 ms 0x00000030 0x00000000 6 CK 0x00000030 0x00000010 6 CK 0x00000030 0x00000020 6 CK, 64 ms 0x0000003f 0x0000002b 0x0000003f 0x00000064 8.0 0x0000003f 0x00000060 0x00000100 0x00000100 Application reset, address $0 0x00000100 0x00000000 Boot loader reset 0x0c000000 0x0c000000 No restrictions for SPM or (E)LPM 0x0c000000 0x08000000 No write to the Application section 0x0c000000 0x00000000 No write to Application section, No read from the Application section 0x0c000000 0x04000000 No read from the Application section 0x30000000 0x30000000 No restrictions for SPM or (E)LPM 0x30000000 0x20000000 No write to the Boot Loader section 0x30000000 0x00000000 No write to Boot Loader section, No read from the Boot Loader section 0x30000000 0x10000000 No read from the Boot Loader section 0x00001000 0x00000000 Watchdog always ON 0x00001000 0x00001000 Watchdog disabled 8 0x00000080 0x00000000 CLKDIV8 Fuse 0x00000080 0x00000080 CLKDIV8 0x00000040 0x00000000 CKOUT Fuse 0x00000040 0x00000040 CKOUT Fuse 0x00060000 0x00060000 BOD disabled 0x00060000 0x00040000 BOD enabled, 1.8 V 0x00060000 0x00020000 BOD enabled, 2.7 V 0x00060000 0x00000000 BOD enabled, 4.0 V AVRSimCoreV2.SimCoreV2 AVRSimMemory8bit.SimMemory8bit AVRSimInterrupt.SimInterrupt 0x28 0 20 AVRSimIOPort.SimIOPort Y AVRSimIOPort.SimIOPort Y AVRSimIOPort.SimIOPort Y AVRSimIOPort.SimIOPort Y AVRSimIOPort.SimIOPort Y AVRSimIOPort.SimIOPort Y AVRSimIOPort.SimIOPort Y AVRSimIOExtInterrupt.SimIOExtInterrupt 0x02 0x1D 0x01 0x1C 0x01 0x09 0x02 0x49 0x03 AVRSimIOPinChangeInterrupt.SimIOPinChangeInterrupt 0x04 0x1D 0x10 0x1C 0x10 0x4b 0x0C 0xff AVRSimIOPinChangeInterrupt.SimIOPinChangeInterrupt 0x06 0x1D 0x20 0x1C 0x20 0x03 0xff 0x4c AvrMasterTimer.MasterTimer 0x08 0x0A PORTB 7 1:8:32:64:128:256:1024 AvrMasterTimer.MasterTimer 0x0C 0x0E 0x10 0x12 0x09 0x01 0x05 0x20 0x05 0x40 TIFR1/OCF1A TIFR1/OCF1B 1:8:64:256:1024 0x23 0x01 AvrMasterTimer.MasterTimer 0x14 0x16 PORTB 4 0x12 0x10 1:8:64:256:1024 AVRSimIOSpi.SimIOSpi 0x18 0x03 0x02 0x03 0x08 0x03 0x04 0x03 0x04 0x01 AVRSimIOSPM.SimIOSPM 0x2a AVRSimIOUsart.SimIOUsart 0x1A 0x1E 0x1C 0x0C 0x02 0x0C 0x01 AVRSimAC.SimIOAC 0x24 AVRSimADC.SimADC 0x26 AvrSimUSI.SimUSI 0x22 0x20 AvrSimLcd.SimLCD 0x2C 0xff 0xff 0xff 0xff