Full datasheet for the ATmega32 AVR microcontroller in PDF form, 2.70 MB. It describes the pinout, memory, clock options, timers, ADC, USART, SPI, TWI, JTAG interface…

Complete datasheet for the ATmega16 AVR microcontroller in a 2.73 MB PDF. Chapters cover the pinout, memory, clock options, timers, ADC, USART, SPI, TWI, JTAG, fuse and…

Datasheet for the older ATmega161 AVR microcontroller, a 1.65 MB PDF document. It details pin functions, the memory map, peripherals such as timers and UARTs…

Complete datasheet for the ATmega8535 AVR microcontroller in a 2.44 MB PDF. It covers the 40-pin and surface-mount pinouts, memory, timers, ADC, USART, SPI, TWI, fuse…

Full Atmel datasheet for the AT89S8253, an 8051-compatible microcontroller with 12 KB of in-system programmable flash and 2 KB of onboard EEPROM.

Datasheet for the Atmel AT89S8252, an 8051-family microcontroller with 8 KB of downloadable flash, 2 KB of EEPROM and an SPI interface used for in-system programming.

Complete datasheet for the Atmel ATmega128, a 64-pin 8-bit AVR microcontroller with 128 KB of flash, EEPROM, SRAM, two USARTs and JTAG.

Atmel datasheet for the AT89C4051, a compact 20-pin 8051-compatible microcontroller with 4 KB of flash and an onboard analog comparator.

PDF datasheet for the Atmel AT89C1051, the smallest member of the 20-pin 8051-compatible family, offering 1 KB of flash, 64 bytes of RAM and an analog comparator.

PDF datasheet for the Atmel AT89S51, an 8051-compatible microcontroller with 4 KB of in-system programmable flash and 128 bytes of RAM.