ATmega8 28-Pin 8-Bit AVR Microcontroller
Classic 28-pin AVR RISC microcontroller with 8KB Flash, 1KB SRAM, 512 bytes EEPROM, 6-channel 10-bit ADC, USART, SPI, I2C (TWI), and 3 PWM channels. Original MCU of the Arduino NG/Severino.
Aliase:ATmega8A, ATmega8-16PU, Classic Arduino MCU
DIP-28 Top View
28 Pins
Pinout Table28
| Pin | Signal / Name | Type | Alternative Functions |
|---|---|---|---|
| 1 | PC6 (~RESET) | Digital | Port C Bit 6 / Master Reset (Active Low) |
| 2 | PD0 (RXD) | Digital | Port D Bit 0 / USART Receive |
| 3 | PD1 (TXD) | Digital | Port D Bit 1 / USART Transmit |
| 4 | PD2 (INT0) | Digital | Port D Bit 2 / External Interrupt 0 |
| 5 | PD3 (INT1) | Digital | Port D Bit 3 / External Interrupt 1 |
| 6 | PD4 (XCK/T0) | Digital | Port D Bit 4 / USART Sync Clock / Timer 0 Clock |
| 7 | VCC | Power | Digital Supply Voltage (+2.7V to +5.5V) |
| 8 | GND | Ground | System Ground (0V) |
| 9 | PB6 (XTAL1) | Digital | Port B Bit 6 / Oscillator 1 / RTC Oscillator 1 |
| 10 | PB7 (XTAL2) | Digital | Port B Bit 7 / Oscillator 2 / RTC Oscillator 2 |
| 11 | PD5 (T1) | Digital | Port D Bit 5 / Timer 1 Clock Input |
| 12 | PD6 (AIN0) | Analog | Port D Bit 6 / Analog Comparator Positive Input |
| 13 | PD7 (AIN1) | Analog | Port D Bit 7 / Analog Comparator Negative Input |
| 14 | PB0 (ICP1) | Digital | Port B Bit 0 / Timer 1 Input Capture |
| 15 | PB1 (OC1A) | Digital | Port B Bit 1 / Timer 1 PWM Output A |
| 16 | PB2 (OC1B/~SS) | Digital | Port B Bit 2 / Timer 1 PWM Output B / SPI Slave Select |
| 17 | PB3 (MOSI/OC2) | Digital | Port B Bit 3 / SPI MOSI / Timer 2 PWM Output |
| 18 | PB4 (MISO) | Digital | Port B Bit 4 / SPI Master In Slave Out |
| 19 | PB5 (SCK) | Digital | Port B Bit 5 / SPI Serial Clock |
| 20 | AVCC | Power | Analog Supply Voltage (+2.7V to +5.5V) |
| 21 | AREF | Analog | Analog Reference Voltage for ADC |
| 22 | GND | Ground | Analog Ground (0V) |
| 23 | PC0 (ADC0) | Analog | Port C Bit 0 / Analog Input Channel 0 |
| 24 | PC1 (ADC1) | Analog | Port C Bit 1 / Analog Input Channel 1 |
| 25 | PC2 (ADC2) | Analog | Port C Bit 2 / Analog Input Channel 2 |
| 26 | PC3 (ADC3) | Analog | Port C Bit 3 / Analog Input Channel 3 |
| 27 | PC4 (ADC4/SDA) | Digital | Port C Bit 4 / Analog Input 4 / I2C Serial Data (SDA) |
| 28 | PC5 (ADC5/SCL) | Digital | Port C Bit 5 / Analog Input 5 / I2C Serial Clock (SCL) |