Full datasheet for the Atmel ATmega169 8-bit AVR microcontroller, with the name indicating coverage of silicon revisions A through E. The ATmega169 integrates an LCD controller, flash, EEPROM and SRAM, and the document details pinout, electrical characteristics, peripherals, registers and per-revision errata. Technicians use it to identify pin functions, check supply and reset pins, and plan ISP or JTAG programming. As a PDF of 3.24 MB it opens in any standard reader; confirm the exact part marking on the chip first.
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