Microchip datasheet for the PIC16F8x devices, the classic 18-pin flash and EEPROM microcontrollers of the PIC16F83 and PIC16F84 type, in a 1.97 MB PDF. It covers pin functions, oscillator modes, the data EEPROM, configuration word and electrical characteristics. Technicians use it to find the MCLR, RB6 and RB7 programming pins for reading or writing firmware, and to check supply and crystal connections. Code protection may block a readback, so save any available dump before erasing a chip that still holds the original program.
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