The Atmel® AVR® ATmega128 is a low-power CMOS 8-bit microcontroller based on the AVR enhanced RISC architecture. By executing powerful instructions in a single clock cycle, the ATmega128 achieves throughputs approaching 1MIPS per MHz allowing the system designer to optimize power consumption versus processing speed.
| Peripheral Features | |
| Programmable I/O Lines | 53 Programmable I/O Lines |
| Timers | Two 8-bit Timer/Counters and Two Expanded 16-bit Timer/Counters with Separate Prescalers and Compare Modes |
| ADC | 8-channel, 10-bit ADC |
| Serial Interface | 2 Programmable Serial USARTs |
| Master / Slave Interface | SPI Serial Interface |
| PWM | Two 8-bit PWM Channels and 6 PWM Channels with Programmable Resolution from 2 to 16 Bits |
| Watch Dog Timer | Programmable Watch Dog Timer With on chip Oscillator |
| Power Supply | |
| Type | DC |
| Operating Voltage | 2.7V - 5.5V |
| Special Features | |
| Internal Oscillator | Internal Calibrated Oscillator |
| External Oscillator | Up to 16 MHz |
| Interrupt Source | External and Internal |
| Clock Frequency Setting | Adjustable through Software |