Microchip datasheet for the PIC18F1220 and PIC18F1320, 18-pin PIC18 flash microcontrollers, about 5.48 MB. It describes the pinout, internal oscillator block, ADC, enhanced USART, timers, configuration registers and electrical specifications of both parts. A technician can use it to locate the in-circuit programming pins, check supply and reset, and decode configuration settings in a firmware image. The two parts differ mainly in program memory size, so confirm which one is fitted before writing a dump to it.
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