AI Interactive Datasheet ATtiny4313
AVR · tinyAVR

ATtiny4313 registers

All 58 registers by peripheral, at their data-space address (the I/O address IN and OUT use is shown beside it), with their reset value and every bit.

AC Analog Comparator

DIDRDigital Input Disable Register 1

Address
0x21 I/O 0x01
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4–
  5. 3–
  6. 2–
  7. 1–
  8. 0–

ACSRAnalog Comparator Control And Status Register

Address
0x28 I/O 0x08
Reset
0x00
Access
read/write
  1. 7ACD
  2. 6ACBG
  3. 5ACO
  4. 4ACI
  5. 3ACIE
  6. 2ACIC
  7. 1ACIS1
  8. 0ACIS0
7 fields
FieldBitsWhat it does
ACD7Analog Comparator Disable
ACBG6Analog Comparator Bandgap Select
ACO5Analog Compare Output
ACI4Analog Comparator Interrupt Flag
ACIE3Analog Comparator Interrupt Enable
ACIC2
ACIS1:0Analog Comparator Interrupt Mode Select bits
  • 0 Interrupt on Toggle
  • 1 Reserved
  • 2 Interrupt on Falling Edge
  • 3 Interrupt on Rising Edge

USART USART

UBRRHUSART Baud Rate Register High Byte

Address
0x22 I/O 0x02
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4–
  5. 3–
  6. 2–
  7. 1–
  8. 0–

UCSRCUSART Control and Status Register C

Address
0x23 I/O 0x03
Reset
0x00
Access
read/write
  1. 7UMSEL1
  2. 6UMSEL0
  3. 5UPM1
  4. 4UPM0
  5. 3USBS
  6. 2UCSZ1
  7. 1UCSZ0
  8. 0UCPOL
5 fields
FieldBitsWhat it does
UMSEL7:6USART Mode Select
  • 0 Asynchronous Operation
  • 1 Synchronous Operation
  • 3 Master SPI
UPM5:4Parity Mode Bits
  • 0 Disabled
  • 1 Reserved
  • 2 Enabled, Even Parity
  • 3 Enabled, Odd Parity
USBS3Stop Bit Select
  • 0 1-bit
  • 1 2-bit
UCSZ2:1Character Size Bits
UCPOL0Clock Polarity

UBRRLUSART Baud Rate Register Low Byte

Address
0x29 I/O 0x09
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4–
  5. 3–
  6. 2–
  7. 1–
  8. 0–

UCSRBUSART Control and Status Register B

Address
0x2A I/O 0x0A
Reset
0x00
Access
read/write
  1. 7RXCIE
  2. 6TXCIE
  3. 5UDRIE
  4. 4RXEN
  5. 3TXEN
  6. 2UCSZ2
  7. 1RXB8
  8. 0TXB8
8 fields
FieldBitsWhat it does
RXCIE7RX Complete Interrupt Enable
TXCIE6TX Complete Interrupt Enable
UDRIE5USART Data register Empty Interrupt Enable
RXEN4Receiver Enable
TXEN3Transmitter Enable
UCSZ22Character Size
RXB81Receive Data Bit 8
TXB80Transmit Data Bit 8

UCSRAUSART Control and Status Register A

Address
0x2B I/O 0x0B
Reset
0x00
Access
read/write
  1. 7RXC
  2. 6TXC
  3. 5UDRE
  4. 4FE
  5. 3DOR
  6. 2UPE
  7. 1U2X
  8. 0MPCM
8 fields
FieldBitsWhat it does
RXC7USART Receive Complete
TXC6USART Transmit Complete
UDRE5USART Data Register Empty
FE4Framing Error
DOR3Data Overrun
UPE2USART Parity Error
U2X1Double the USART Transmission Speed
MPCM0Multi-processor Communication Mode

UDRUSART I/O Data Register

Address
0x2C I/O 0x0C
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4–
  5. 3–
  6. 2–
  7. 1–
  8. 0–

EXINT External Interrupts

PCMSK1Pin Change Interrupt Mask Register 1

Address
0x24 I/O 0x04
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4–
  5. 3–
  6. 2PCINT2
  7. 1PCINT1
  8. 0PCINT0
1 field
FieldBitsWhat it does
PCINT2:0Pin Change Interrupt Masks

PCMSK2Pin Change Interrupt Mask Register 2

Address
0x25 I/O 0x05
Reset
0x00
Access
read/write
  1. 7–
  2. 6PCINT6
  3. 5PCINT5
  4. 4PCINT4
  5. 3PCINT3
  6. 2PCINT2
  7. 1PCINT1
  8. 0PCINT0
1 field
FieldBitsWhat it does
PCINT6:0Pin Change Interrupt Masks

PCMSK0Pin Change Interrupt Mask Register 0

Address
0x40 I/O 0x20
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4–
  5. 3–
  6. 2–
  7. 1–
  8. 0–

GIFRGeneral Interrupt Flag Register

Address
0x5A I/O 0x3A
Reset
0x00
Access
read/write
  1. 7INTF1
  2. 6INTF0
  3. 5PCIF2
  4. 4PCIF1
  5. 3PCIF0
  6. 2–
  7. 1–
  8. 0–
2 fields
FieldBitsWhat it does
INTF7:6External Interrupt Flags
PCIF5:3Pin Change Interrupt Flags

GIMSKGeneral Interrupt Mask Register

Address
0x5B I/O 0x3B
Reset
0x00
Access
read/write
  1. 7INT1
  2. 6INT0
  3. 5PCIE
  4. 4–
  5. 3–
  6. 2–
  7. 1–
  8. 0–
2 fields
FieldBitsWhat it does
INT7:6External Interrupt Request 1 Enable
PCIE5

CPU CPU Registers

PRRPower reduction register

Address
0x26 I/O 0x06
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4–
  5. 3PRTIM1
  6. 2PRTIM0
  7. 1PRUSI
  8. 0PRUSART
3 fields
FieldBitsWhat it does
PRTIM3:2
PRUSI1
PRUSART0

BODCRBOD control register

Address
0x27 I/O 0x07
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4–
  5. 3–
  6. 2–
  7. 1BPDS
  8. 0BPDSE
2 fields
FieldBitsWhat it does
BPDS1
BPDSE0

GPIOR0General Purpose I/O Register 0

Address
0x33 I/O 0x13
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4–
  5. 3–
  6. 2–
  7. 1–
  8. 0–

GPIOR1General Purpose I/O Register 1

Address
0x34 I/O 0x14
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4–
  5. 3–
  6. 2–
  7. 1–
  8. 0–

GPIOR2General Purpose I/O Register 2

Address
0x35 I/O 0x15
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4–
  5. 3–
  6. 2–
  7. 1–
  8. 0–

GTCCRGeneral Timer Counter Control Register

Address
0x43 I/O 0x23
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4–
  5. 3–
  6. 2–
  7. 1–
  8. 0PSR10
1 field
FieldBitsWhat it does
PSR100

CLKPRClock Prescale Register

Address
0x46 I/O 0x26
Reset
0x00
Access
read/write
  1. 7CLKPCE
  2. 6–
  3. 5–
  4. 4–
  5. 3CLKPS3
  6. 2CLKPS2
  7. 1CLKPS1
  8. 0CLKPS0
2 fields
FieldBitsWhat it does
CLKPCE7Clock Prescaler Change Enable
CLKPS3:0Clock Prescaler Select Bits
  • 0 1
  • 1 2
  • 2 4
  • 3 8
  • 4 16
  • 5 32
  • 6 64
  • 7 128
  • 8 256

OSCCALOscillator Calibration Register

Address
0x51 I/O 0x31
Reset
0x00
Access
read/write
  1. 7OSCCAL7
  2. 6OSCCAL6
  3. 5OSCCAL5
  4. 4OSCCAL4
  5. 3OSCCAL3
  6. 2OSCCAL2
  7. 1OSCCAL1
  8. 0OSCCAL0
1 field
FieldBitsWhat it does
OSCCAL7:0Oscillator Calibration

MCUSRMCU Status register

Address
0x54 I/O 0x34
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4–
  5. 3WDRF
  6. 2BORF
  7. 1EXTRF
  8. 0PORF
4 fields
FieldBitsWhat it does
WDRF3Watchdog Reset Flag
BORF2Brown-out Reset Flag
EXTRF1External Reset Flag
PORF0Power-On Reset Flag

MCUCRMCU Control Register

Address
0x55 I/O 0x35
Reset
0x00
Access
read/write
  1. 7PUD
  2. 6SM2
  3. 5SE
  4. 4SM0
  5. 3ISC11
  6. 2ISC10
  7. 1ISC01
  8. 0ISC00
5 fields
FieldBitsWhat it does
PUD7Pull-up Disable
SM6,4Sleep Mode Select Bits
  • 0 Idle
  • 1 Power Down
  • 4 Standby
  • 5 Power Down
SE5Sleep Enable
ISC13:2Interrupt Sense Control 1 bits
  • 0 Low Level of INTX
  • 1 Any Logical Change in INTX
  • 2 Falling Edge of INTX
  • 3 Rising Edge of INTX
ISC01:0Interrupt Sense Control 0 bits
  • 0 Low Level of INTX
  • 1 Any Logical Change in INTX
  • 2 Falling Edge of INTX
  • 3 Rising Edge of INTX

SPMCSRStore Program Memory Control and Status register

Address
0x57 I/O 0x37
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4CTPB
  5. 3RFLB
  6. 2PGWRT
  7. 1PGERS
  8. 0SPMEN
5 fields
FieldBitsWhat it does
CTPB4Clear Temporary Page Buffer
RFLB3Read Fuse and Lock Bits
PGWRT2Page Write
PGERS1Page Erase
SPMEN0Store Program Memory Enable

SPStack Pointer

Address
0x5D I/O 0x3D
Reset
0x015F
Access
read/write
Size
16-bit

SREGStatus Register

Address
0x5F I/O 0x3F
Reset
0x00
Access
read/write
  1. 7I
  2. 6T
  3. 5H
  4. 4S
  5. 3V
  6. 2N
  7. 1Z
  8. 0C
8 fields
FieldBitsWhat it does
I7Global Interrupt Enable
T6Bit Copy Storage
H5Half Carry Flag
S4Sign Bit
V3Two's Complement Overflow Flag
N2Negative Flag
Z1Zero Flag
C0Carry Flag

USI Universal Serial Interface

USICRUSI Control Register

Address
0x2D I/O 0x0D
Reset
0x00
Access
read/write
  1. 7USISIE
  2. 6USIOIE
  3. 5USIWM1
  4. 4USIWM0
  5. 3USICS1
  6. 2USICS0
  7. 1USICLK
  8. 0USITC
6 fields
FieldBitsWhat it does
USISIE7Start Condition Interrupt Enable
USIOIE6Counter Overflow Interrupt Enable
USIWM5:4USI Wire Mode Bits
  • 0 Normal Operation
  • 1 Three-Wire Mode
  • 2 Two-Wire Mode
  • 3 Two-Wire Mode Held Low
USICS3:2USI Clock Source Select Bits
USICLK1Clock Strobe
USITC0Toggle Clock Port Pin

USISRUSI Status Register

Address
0x2E I/O 0x0E
Reset
0x00
Access
read/write
  1. 7USISIF
  2. 6USIOIF
  3. 5USIPF
  4. 4USIDC
  5. 3USICNT3
  6. 2USICNT2
  7. 1USICNT1
  8. 0USICNT0
5 fields
FieldBitsWhat it does
USISIF7Start Condition Interrupt Flag
USIOIF6Counter Overflow Interrupt Flag
USIPF5Stop Condition Flag
USIDC4Data Output Collision
USICNT3:0USI Counter Value Bits

USIDRUSI Data Register

Address
0x2F I/O 0x0F
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4–
  5. 3–
  6. 2–
  7. 1–
  8. 0–

PORTD I/O Port

PINDInput Pins, Port D

Address
0x30 I/O 0x10
Reset
0x00
Access
read/write
  1. 7–
  2. 6PIND6
  3. 5PIND5
  4. 4PIND4
  5. 3PIND3
  6. 2PIND2
  7. 1PIND1
  8. 0PIND0

DDRDData Direction Register, Port D

Address
0x31 I/O 0x11
Reset
0x00
Access
read/write
  1. 7–
  2. 6DDD6
  3. 5DDD5
  4. 4DDD4
  5. 3DDD3
  6. 2DDD2
  7. 1DDD1
  8. 0DDD0

PORTDData Register, Port D

Address
0x32 I/O 0x12
Reset
0x00
Access
read/write
  1. 7–
  2. 6PORTD6
  3. 5PORTD5
  4. 4PORTD4
  5. 3PORTD3
  6. 2PORTD2
  7. 1PORTD1
  8. 0PORTD0

PORTB I/O Port

PINBPort B Input Pins

Address
0x36 I/O 0x16
Reset
0x00
Access
read/write
  1. 7PINB7
  2. 6PINB6
  3. 5PINB5
  4. 4PINB4
  5. 3PINB3
  6. 2PINB2
  7. 1PINB1
  8. 0PINB0

DDRBPort B Data Direction Register

Address
0x37 I/O 0x17
Reset
0x00
Access
read/write
  1. 7DDB7
  2. 6DDB6
  3. 5DDB5
  4. 4DDB4
  5. 3DDB3
  6. 2DDB2
  7. 1DDB1
  8. 0DDB0

PORTBPort B Data Register

Address
0x38 I/O 0x18
Reset
0x00
Access
read/write
  1. 7PORTB7
  2. 6PORTB6
  3. 5PORTB5
  4. 4PORTB4
  5. 3PORTB3
  6. 2PORTB2
  7. 1PORTB1
  8. 0PORTB0

PORTA I/O Port

PINAPort A Input Pins

Address
0x39 I/O 0x19
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4–
  5. 3–
  6. 2PINA2
  7. 1PINA1
  8. 0PINA0

DDRAPort A Data Direction Register

Address
0x3A I/O 0x1A
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4–
  5. 3–
  6. 2DDA2
  7. 1DDA1
  8. 0DDA0

PORTAPort A Data Register

Address
0x3B I/O 0x1B
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4–
  5. 3–
  6. 2PORTA2
  7. 1PORTA1
  8. 0PORTA0

EEPROM EEPROM

EECREEPROM Control Register

Address
0x3C I/O 0x1C
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5EEPM1
  4. 4EEPM0
  5. 3EERIE
  6. 2EEMPE
  7. 1EEPE
  8. 0EERE
5 fields
FieldBitsWhat it does
EEPM5:4
  • 0 Erase and Write in one operation
  • 1 Erase Only
  • 2 Write Only
EERIE3EEProm Ready Interrupt Enable
EEMPE2EEPROM Master Write Enable
EEPE1EEPROM Write Enable
EERE0EEPROM Read Enable

EEDREEPROM Data Register

Address
0x3D I/O 0x1D
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4–
  5. 3–
  6. 2–
  7. 1–
  8. 0–

EEAREEPROM Read/Write Access

Address
0x3E I/O 0x1E
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4–
  5. 3–
  6. 2–
  7. 1–
  8. 0–

WDT Watchdog Timer

WDTCRWatchdog Timer Control Register

Address
0x41 I/O 0x21
Reset
0x00
Access
read/write
  1. 7WDIF
  2. 6WDIE
  3. 5WDP5
  4. 4WDCE
  5. 3WDE
  6. 2WDP2
  7. 1WDP1
  8. 0WDP0
5 fields
FieldBitsWhat it does
WDIF7Watchdog Timeout Interrupt Flag
WDIE6Watchdog Timeout Interrupt Enable
WDP5,2,1,0Watchdog Timer Prescaler Bits
  • 0 Oscillator Cycles 2K
  • 1 Oscillator Cycles 4K
  • 2 Oscillator Cycles 8K
  • 3 Oscillator Cycles 16K
  • 4 Oscillator Cycles 32K
  • 5 Oscillator Cycles 64K
  • 6 Oscillator Cycles 128K
  • 7 Oscillator Cycles 256K
  • 8 Oscillator Cycles 512K
  • 9 Oscillator Cycles 1024K
WDCE4Watchdog Change Enable
WDE3Watch Dog Enable

TC1 Timer/Counter, 16-bit

TCCR1CTimer/Counter1 Control Register C

Address
0x42 I/O 0x22
Reset
0x00
Access
read/write
  1. 7FOC1A
  2. 6FOC1B
  3. 5–
  4. 4–
  5. 3–
  6. 2–
  7. 1–
  8. 0–
2 fields
FieldBitsWhat it does
FOC1A7Force Output Compare for Channel A
FOC1B6Force Output Compare for Channel B

ICR1Timer/Counter1 Input Capture Register Bytes

Address
0x44 I/O 0x24
Reset
0x0000
Access
read/write
Size
16-bit

OCR1BTimer/Counter1 Output Compare Register Bytes

Address
0x48 I/O 0x28
Reset
0x0000
Access
read/write
Size
16-bit

OCR1ATimer/Counter1 Output Compare Register Bytes

Address
0x4A I/O 0x2A
Reset
0x0000
Access
read/write
Size
16-bit

TCNT1Timer/Counter1 Bytes

Address
0x4C I/O 0x2C
Reset
0x0000
Access
read/write
Size
16-bit

TCCR1BTimer/Counter1 Control Register B

Address
0x4E I/O 0x2E
Reset
0x00
Access
read/write
  1. 7ICNC1
  2. 6ICES1
  3. 5–
  4. 4WGM11
  5. 3WGM10
  6. 2CS12
  7. 1CS11
  8. 0CS10
4 fields
FieldBitsWhat it does
ICNC17Input Capture 1 Noise Canceler
ICES16Input Capture 1 Edge Select
WGM14:3Waveform Generation Mode Bits
CS12:0Clock Select1 bits
  • 0 No Clock Source (Stopped)
  • 1 Running, No Prescaling
  • 2 Running, CLK/8
  • 3 Running, CLK/64
  • 4 Running, CLK/256
  • 5 Running, CLK/1024
  • 6 Running, ExtClk Tn Falling Edge
  • 7 Running, ExtClk Tn Rising Edge

TCCR1ATimer/Counter1 Control Register A

Address
0x4F I/O 0x2F
Reset
0x00
Access
read/write
  1. 7COM1A1
  2. 6COM1A0
  3. 5COM1B1
  4. 4COM1B0
  5. 3–
  6. 2–
  7. 1WGM11
  8. 0WGM10
3 fields
FieldBitsWhat it does
COM1A7:6Compare Output Mode 1A, bits
COM1B5:4Compare Output Mode 1B, bits
WGM11:0Pulse Width Modulator Select Bits

TIFRTimer/Counter Interrupt Flag register

Address
0x58 I/O 0x38
Reset
0x00
Access
read/write
  1. 7TOV1
  2. 6OCF1A
  3. 5OCF1B
  4. 4–
  5. 3ICF1
  6. 2–
  7. 1–
  8. 0–
4 fields
FieldBitsWhat it does
TOV17Timer/Counter1 Overflow Flag
OCF1A6Output Compare Flag 1A
OCF1B5Output Compare Flag 1B
ICF13Input Capture Flag 1

TIMSKTimer/Counter Interrupt Mask Register

Address
0x59 I/O 0x39
Reset
0x00
Access
read/write
  1. 7TOIE1
  2. 6OCIE1A
  3. 5OCIE1B
  4. 4–
  5. 3ICIE1
  6. 2–
  7. 1–
  8. 0–
4 fields
FieldBitsWhat it does
TOIE17Timer/Counter1 Overflow Interrupt Enable
OCIE1A6Timer/Counter1 Output CompareA Match Interrupt Enable
OCIE1B5Timer/Counter1 Output CompareB Match Interrupt Enable
ICIE13Timer/Counter1 Input Capture Interrupt Enable

TC0 Timer/Counter, 8-bit

TCCR0ATimer/Counter Control Register A

Address
0x50 I/O 0x30
Reset
0x00
Access
read/write
  1. 7COM0A1
  2. 6COM0A0
  3. 5COM0B1
  4. 4COM0B0
  5. 3–
  6. 2–
  7. 1WGM01
  8. 0WGM00
3 fields
FieldBitsWhat it does
COM0A7:6Compare Match Output A Mode
COM0B5:4Compare Match Output B Mode
WGM01:0Waveform Generation Mode

TCNT0Timer/Counter0

Address
0x52 I/O 0x32
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4–
  5. 3–
  6. 2–
  7. 1–
  8. 0–

TCCR0BTimer/Counter Control Register B

Address
0x53 I/O 0x33
Reset
0x00
Access
read/write
  1. 7FOC0A
  2. 6FOC0B
  3. 5–
  4. 4–
  5. 3WGM02
  6. 2CS02
  7. 1CS01
  8. 0CS00
4 fields
FieldBitsWhat it does
FOC0A7Force Output Compare B
FOC0B6Force Output Compare B
WGM023
CS02:0Clock Select
  • 0 No Clock Source (Stopped)
  • 1 Running, No Prescaling
  • 2 Running, CLK/8
  • 3 Running, CLK/64
  • 4 Running, CLK/256
  • 5 Running, CLK/1024
  • 6 Running, ExtClk Tn Falling Edge
  • 7 Running, ExtClk Tn Rising Edge

OCR0ATimer/Counter0 Output Compare Register

Address
0x56 I/O 0x36
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4–
  5. 3–
  6. 2–
  7. 1–
  8. 0–

TIFRTimer/Counter Interrupt Flag register

Address
0x58 I/O 0x38
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4–
  5. 3–
  6. 2OCF0B
  7. 1TOV0
  8. 0OCF0A
3 fields
FieldBitsWhat it does
OCF0B2Timer/Counter0 Output Compare Flag 0B
TOV01Timer/Counter0 Overflow Flag
OCF0A0Timer/Counter0 Output Compare Flag 0A

TIMSKTimer/Counter Interrupt Mask Register

Address
0x59 I/O 0x39
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4–
  5. 3–
  6. 2OCIE0B
  7. 1TOIE0
  8. 0OCIE0A
3 fields
FieldBitsWhat it does
OCIE0B2Timer/Counter0 Output Compare Match B Interrupt Enable
TOIE01Timer/Counter0 Overflow Interrupt Enable
OCIE0A0Timer/Counter0 Output Compare Match A Interrupt Enable

OCR0BTimer/Counter0 Output Compare Register

Address
0x5C I/O 0x3C
Reset
0x00
Access
read/write
  1. 7–
  2. 6–
  3. 5–
  4. 4–
  5. 3–
  6. 2–
  7. 1–
  8. 0–