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…

Microchip datasheet in PDF format, 2.87 MB, for the PIC16F872 flash microcontroller, a 28-pin member of the PIC16F87x line.

PDF datasheet, 2.54 MB, for the Microchip PIC16F72 flash microcontroller with an 8-bit ADC and capture, compare and PWM module.

Atmel datasheet covering the AT24C32 and AT24C64 serial EEPROMs, 32 Kbit and 64 Kbit two-wire I2C memories.