Overview
The 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 1 MIPS per MHz allowing the system designer to optimize power consumption versus processing speed.

FEATUREs
• High-performance, Low-power AVR® 8-bit Microcontroller
• Advanced RISC Architecture
    – 133 Powerful Instructions – Most Single Clock Cycle Execution
    – 32 x 8 General Purpose Working Registers + Peripheral Control Registers
    – Fully Static Operation
    – Up to 16 MIPS Throughput at 16 MHz
    – On-chip 2-cycle Multiplier
• Nonvolatile Program and Data Memories
    – 128K Bytes of In-System Reprogrammable Flash Endurance: 1,000 Write/Erase Cycles
    – Optional Boot Code Section with Independent Lock Bits In-System Programming by On-chip Boot Program True Read-While-Write Operation
    – 4K Bytes EEPROM Endurance: 100,000 Write/Erase Cycles
    – 4K Bytes Internal SRAM
    – Up to 64K Bytes Optional External Memory Space
    – Programming Lock for Software Security
    – SPI Interface for In-System Programming
• JTAG (IEEE std. 1149.1 Compliant) Interface
    – Boundary-scan Capabilities According to the JTAG Standard
    – Extensive On-chip Debug Support
    – Programming of Flash, EEPROM, Fuses and Lock Bits through the JTAG Interface
• Peripheral Features
    – Two 8-bit Timer/Counters with Separate Prescalers and Compare Modes
    – Two Expanded 16-bit Timer/Counters with Separate Prescaler, Compare Mode and Capture Mode
    – Real Time Counter with Separate Oscillator
    – Two 8-bit PWM Channels
    – 6 PWM Channels with Programmable Resolution from 1 to 16 Bits
    – 8-channel, 10-bit ADC 8 Single-ended Channels 7 Differential Channels 2 Differential Channels with Programmable Gain (1x, 10x, 200x)
    – Byte-oriented 2-wire Serial Interface
    – Dual Programmable Serial USARTs
    – Master/Slave SPI Serial Interface
    – Programmable Watchdog Timer with On-chip Oscillator
    – On-chip Analog Comparator
• Special Microcontroller Features
    – Power-on Reset and Programmable Brown-out Detection
    – Internal Calibrated RC Oscillator
    – External and Internal Interrupt Sources
    – Six Sleep Modes: Idle, ADC Noise Reduction, Power-save, Power-down, Standby and Extended Standby
    – Software Selectable Clock Frequency
    – ATmega103 Compatibility Mode Selected by a Fuse
    – Global Pull-up Disable
• I/O and Packages
    – 53 Programmable I/O Lines
    – 64-lead TQFP
• Operating Voltages
    – 2.7 - 5.5V (ATmega128L)
    – 4.5 - 5.5V (ATmega128)
• Speed Grades
    – 0 - 8 MHz (ATmega128L)
    – 0 - 16 MHz (ATmega128)