Datasheet for the Microchip PIC16F870 and PIC16F871 flash microcontrollers, a 2.76 MB PDF. The two devices share one document, the 870 coming in a 28-pin package and the 871 in a 40-pin package. Technicians use it to identify supply, MCLR, oscillator and ICSP programming pins, review configuration bits and check analog inputs. Since these are flash parts, they can be reprogrammed in-circuit with a suitable PIC programmer, but read and save any existing code first if it is not protected.
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