343

2545M–AVR–09/07

ATmega48/88/168

30. Register Summary

Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Page

(0xFF) Reserved – – – – – – – –

(0xFE) Reserved – – – – – – – –

(0xFD) Reserved – – – – – – – –

(0xFC) Reserved

– – – – – – – –

(0xFB) Reserved

– – – – – – – –

(0xFA) Reserved – – – – – – – –

(0xF9) Reserved – – – – – – – –

(0xF8) Reserved – – – – – – – –

(0xF7) Reserved – – – – – – – –

(0xF6) Reserved – – – – – – – –

(0xF5) Reserved – – – – – – – –

(0xF4) Reserved – – – – – – – –

(0xF3) Reserved – – – – – – – –

(0xF2) Reserved – – – – – – – –

(0xF1) Reserved – – – – – – – –

(0xF0) Reserved

– – – – – – – –

(0xEF) Reserved

– – – – – – – –

(0xEE) Reserved – – – – – – – –

(0xED) Reserved – – – – – – – –

(0xEC) Reserved – – – – – – – –

(0xEB) Reserved – – – – – – – –

(0xEA) Reserved – – – – – – – –

(0xE9) Reserved – – – – – – – –

(0xE8) Reserved – – – – – – – –

(0xE7) Reserved – – – – – – – –

(0xE6) Reserved – – – – – – – –

(0xE5) Reserved – – – – – – – –

(0xE4) Reserved – – – – – – – –

(0xE3) Reserved – – – – – – – –

(0xE2) Reserved – – – – – – – –

(0xE1) Reserved – – – – – – – –

(0xE0) Reserved – – – – – – – –

(0xDF) Reserved – – – – – – – –

(0xDE) Reserved – – – – – – – –

(0xDD) Reserved – – – – – – – –

(0xDC) Reserved – – – – – – – –

(0xDB) Reserved – – – – – – – –

(0xDA) Reserved – – – – – – – –

(0xD9) Reserved – – – – – – – –

(0xD8) Reserved – – – – – – – –

(0xD7) Reserved – – – – – – – –

(0xD6) Reserved – – – – – – – –

(0xD5) Reserved

– – – – – – – –

(0xD4) Reserved

– – – – – – – –

(0xD3) Reserved – – – – – – – –

(0xD2) Reserved

– – – – – – – –

(0xD1) Reserved

– – – – – – – –

(0xD0) Reserved

– – – – – – – –

(0xCF) Reserved – – – – – – – –

(0xCE) Reserved

– – – – – – – –

(0xCD) Reserved

– – – – – – – –

(0xCC) Reserved – – – – – – – –

(0xCB) Reserved

– – – – – – – –

(0xCA) Reserved

– – – – – – – –

(0xC9) Reserved – – – – – – – –

(0xC8) Reserved

– – – – – – – –

(0xC7) Reserved

– – – – – – – –

(0xC6) UDR0 USART I/O Data Register 191

(0xC5) UBRR0H

USART Baud Rate Register High 195

(0xC4) UBRR0L USART Baud Rate Register Low 195

(0xC3) Reserved

– – – – – – – –

(0xC2) UCSR0C UMSEL01 UMSEL00 UPM01 UPM00 USBS0

UCSZ01 /UDORD0 UCSZ00 / UCPHA0

UCPOL0 193/208

(0xC1) UCSR0B RXCIE0 TXCIE0 UDRIE0 RXEN0 TXEN0 UCSZ02 RXB80 TXB80 192

(0xC0) UCSR0A RXC0 TXC0 UDRE0 FE0 DOR0 UPE0 U2X0 MPCM0 191

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2545M–AVR–09/07

ATmega48/88/168

(0xBF) Reserved – – – – – – – –

(0xBE) Reserved – – – – – – – –

(0xBD) TWAMR TWAM6 TWAM5 TWAM4 TWAM3 TWAM2 TWAM1 TWAM0 –240

(0xBC) TWCR TWINT TWEA TWSTA TWSTO TWWC TWEN –TWIE 237

(0xBB) TWDR 2-wire Serial Interface Data Register 239

(0xBA) TWAR TWA6 TWA5 TWA4 TWA3 TWA2 TWA1 TWA0 TWGCE 240

(0xB9) TWSR TWS7 TWS6 TWS5 TWS4 TWS3 –TWPS1TWPS0 239

(0xB8) TWBR 2-wire Serial Interface Bit Rate Register 237

(0xB7) Reserved – – – – – – –

(0xB6) ASSR – EXCLK AS2 TCN2UB OCR2AUB OCR2BUB TCR2AUB TCR2BUB 160

(0xB5) Reserved – – – – – – – –

(0xB4) OCR2B Timer/Counter2 Output Compare Register B 159

(0xB3) OCR2A Timer/Counter2 Output Compare Register A 158

(0xB2) TCNT2 Timer/Counter2 (8-bit) 158

(0xB1) TCCR2B FOC2A FOC2B – – WGM22 CS22 CS21 CS20

157

(0xB0) TCCR2A COM2A1 COM2A0 COM2B1 COM2B0 – –WGM21WGM20 154

(0xAF) Reserved

– – – – – – – –

(0xAE) Reserved

– – – – – – – –

(0xAD) Reserved – – – – – – – –

(0xAC) Reserved

– – – – – – – –

(0xAB) Reserved

– – – – – – – –

(0xAA) Reserved – – – – – – – –

(0xA9) Reserved – – – – – – – –

(0xA8) Reserved – – – – – – – –

(0xA7) Reserved – – – – – – – –

(0xA6) Reserved – – – – – – – –

(0xA5) Reserved – – – – – – – –

(0xA4) Reserved – – – – – – – –

(0xA3) Reserved – – – – – – – –

(0xA2) Reserved – – – – – – – –

(0xA1) Reserved – – – – – – – –

(0xA0) Reserved – – – – – – – –

(0x9F) Reserved – – – – – – – –

(0x9E) Reserved – – – – – – – –

(0x9D) Reserved – – – – – – – –

(0x9C) Reserved – – – – – – – –

(0x9B) Reserved – – – – – – – –

(0x9A) Reserved – – – – – – – –

(0x99) Reserved – – – – – – – –

(0x98) Reserved – – – – – – – –

(0x97) Reserved – – – – – – – –

(0x96) Reserved – – – – – – – –

(0x95) Reserved – – – – – – – –

(0x94) Reserved

– – – – – – – –

(0x93) Reserved

– – – – – – – –

(0x92) Reserved – – – – – – – –

(0x91) Reserved

– – – – – – – –

(0x90) Reserved

– – – – – – – –

(0x8F) Reserved

– – – – – – – –

(0x8E) Reserved – – – – – – – –

(0x8D) Reserved

– – – – – – – –

(0x8C) Reserved

– – – – – – – –

(0x8B) OCR1BH Timer/Counter1 - Output Compare Register B High Byte 135

(0x8A) OCR1BL Timer/Counter1 - Output Compare Register B Low Byte 135

(0x89) OCR1AH Timer/Counter1 - Output Compare Register A High Byte 135

(0x88) OCR1AL Timer/Counter1 - Output Compare Register A Low Byte 135

(0x87) ICR1H Timer/Counter1 - Input Capture Register High Byte 136

(0x86) ICR1L Timer/Counter1 - Input Capture Register Low Byte 136

(0x85) TCNT1H Timer/Counter1 - Counter Register High Byte 135

(0x84) TCNT1L Timer/Counter1 - Counter Register Low Byte 135

(0x83) Reserved

– – – – – – – –

(0x82) TCCR1C FOC1A FOC1B

– – – – – –134

(0x81) TCCR1B ICNC1 ICES1

– WGM13 WGM12 CS12 CS11 CS10 133

(0x80) TCCR1A COM1A1 COM1A0 COM1B1 COM1B0 – –WGM11WGM10 131

(0x7F) DIDR1

– – – – – –AIN1DAIN0D 244

(0x7E) DIDR0

– – ADC5D ADC4D ADC3D ADC2D ADC1D ADC0D 260

Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Page

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2545M–AVR–09/07

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(0x7D) Reserved – – – – – – – –

(0x7C) ADMUX REFS1 REFS0 ADLAR – MUX3 MUX2 MUX1 MUX0 256

(0x7B) ADCSRB –ACME – – – ADTS2 ADTS1 ADTS0 259

(0x7A) ADCSRA ADEN ADSC ADATE ADIF ADIE ADPS2 ADPS1 ADPS0 257

(0x79) ADCH ADC Data Register High byte 259

(0x78) ADCL ADC Data Register Low byte 259

(0x77) Reserved – – – – – – – –

(0x76) Reserved – – – – – – – –

(0x75) Reserved – – – – – – – –

(0x74) Reserved – – – – – – – –

(0x73) Reserved – – – – – – – –

(0x72) Reserved – – – – – – – –

(0x71) Reserved – – – – – – – –

(0x70) TIMSK2 – – – – – OCIE2B OCIE2A TOIE2 159

(0x6F) TIMSK1 – –ICIE1 – – OCIE1B OCIE1A TOIE1 136

(0x6E) TIMSK0 – – – – – OCIE0B OCIE0A TOIE0 107

(0x6D) PCMSK2 PCINT23 PCINT22 PCINT21 PCINT20 PCINT19 PCINT18 PCINT17 PCINT16 71

(0x6C) PCMSK1 – PCINT14 PCINT13 PCINT12 PCINT11 PCINT10 PCINT9 PCINT8 71

(0x6B) PCMSK0 PCINT7 PCINT6 PCINT5 PCINT4 PCINT3 PCINT2 PCINT1 PCINT0 71

(0x6A) Reserved

– – – – – – – –

(0x69) EICRA

– – – –ISC11ISC10ISC01ISC00 68

(0x68) PCICR – – – – – PCIE2 PCIE1 PCIE0

(0x67) Reserved – – – – – – – –

(0x66) OSCCAL Oscillator Calibration Register 38

(0x65) Reserved – – – – – – – –

(0x64) PRR PRTWI PRTIM2 PRTIM0 – PRTIM1 PRSPI PRUSART0 PRADC 42

(0x63) Reserved – – – – – – – –

(0x62) Reserved – – – – – – – –

(0x61) CLKPR CLKPCE – – – CLKPS3 CLKPS2 CLKPS1 CLKPS0 38

(0x60) WDTCSR WDIF WDIE WDP3 WDCE WDE WDP2 WDP1 WDP0 54

0x3F (0x5F) SREG I T H S V N Z C 12

0x3E (0x5E) SPH – – – – – (SP10)

SP9 SP8 14

0x3D (0x5D) SPL SP7 SP6 SP5 SP4 SP3 SP2 SP1 SP0 14

0x3C (0x5C) Reserved – – – – – – – –

0x3B (0x5B) Reserved – – – – – – – –

0x3A (0x5A) Reserved – – – – – – – –

0x39 (0x59) Reserved – – – – – – – –

0x38 (0x58) Reserved – – – – – – – –

0x37 (0x57) SPMCSR SPMIE (RWWSB)

– (RWWSRE)

BLBSET PGWRT PGERS SELFPRGEN 284

0x36 (0x56) Reserved – – – – – – – –

0x35 (0x55) MCUCR – – –PUD– – IVSEL IVCE

0x34 (0x54) MCUSR – – – – WDRF BORF EXTRF PORF

0x33 (0x53) SMCR – – – –SM2SM1SM0SE 40

0x32 (0x52) Reserved

– – – – – – – –

0x31 (0x51) Reserved

– – – – – – – –

0x30 (0x50) ACSR ACD ACBG ACO ACI ACIE ACIC ACIS1 ACIS0 243

0x2F (0x4F) Reserved

– – – – – – – –

0x2E (0x4E) SPDR SPI Data Register 171

0x2D (0x4D) SPSR SPIF WCOL – – – – – SPI2X 170

0x2C (0x4C) SPCR SPIE SPE DORD MSTR CPOL CPHA SPR1 SPR0 169

0x2B (0x4B) GPIOR2 General Purpose I/O Register 2 27

0x2A (0x4A) GPIOR1 General Purpose I/O Register 1 27

0x29 (0x49) Reserved – – – – – – – –

0x28 (0x48) OCR0B Timer/Counter0 Output Compare Register B

0x27 (0x47) OCR0A Timer/Counter0 Output Compare Register A

0x26 (0x46) TCNT0 Timer/Counter0 (8-bit)

0x25 (0x45) TCCR0B FOC0A FOC0B

– – WGM02 CS02 CS01 CS00

0x24 (0x44) TCCR0A COM0A1 COM0A0 COM0B1 COM0B0

– –WGM01WGM00

0x23 (0x43) GTCCR TSM – – – – – PSRASY PSRSYNC 140/161

0x22 (0x42) EEARH (EEPROM Address Register High Byte)

0x21 (0x41) EEARL EEPROM Address Register Low Byte 23

0x20 (0x40) EEDR EEPROM Data Register 23

0x1F (0x3F) EECR – – EEPM1 EEPM0 EERIE EEMPE EEPE EERE 23

0x1E (0x3E) GPIOR0 General Purpose I/O Register 0 27

0x1D (0x3D) EIMSK

– – – – – –INT1INT0 69

0x1C (0x3C) EIFR

– – – – – – INTF1 INTF0 69

Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Page

Part #	ATMEGA48-20AU
Description	MCU 8BIT ATMEGA RISC 4KB FLASH 3.3V/5V 32TQFP - Trays
Category	IC
Availability	Out of Stock
Qty	0

ATMEGA48-20AU

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