Complete datasheet for the ATmega162 AVR microcontroller in a 2.62 MB PDF. The document describes pin assignments, the external memory interface, timers, USARTs, the SPI and JTAG interfaces, and electrical limits. Repair work uses it to locate VCC, GND, reset and oscillator pins, verify signal levels with a scope or meter, and set fuses correctly when reflashing the part through ISP or JTAG. Compare the exact marking on the chip, including suffix, with the ordering information listed.
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