Complete datasheet for the ATmega165 AVR microcontroller, a 3.15 MB PDF. The document covers the pinout, memory, clock system, timers, USI, USART, ADC, JTAG, fuse bits and electrical characteristics. It is used to locate power, reset, crystal and programming pins, check analog reference wiring and confirm correct fuse configuration before reflashing. Make sure the marking and package on the chip match the ordering information in the document, and save the original contents before writing anything new.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @datasheet. Enginerys does not host this file.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.