Full datasheet for the ATmega329, ATmega3290, ATmega649 and ATmega6490 AVR microcontrollers, a 3.27 MB PDF. These parts integrate an LCD driver, and the higher-numbered 3290 and 6490 versions come in larger pin-count packages with more segment lines. Technicians use it to map LCD, port, power and JTAG or ISP pins for the exact package fitted and to set fuses before reflashing. Verify the device marking and pin count first, as pin tables differ between the variants.
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