Combined datasheet for the Microchip PIC16C63A, PIC16C65B, PIC16C73B and PIC16C74B microcontrollers, provided as a 2.18 MB PDF. These parts share a core and differ mainly in memory size, analog-to-digital converter presence and pin count, so one document serves all four. Repair technicians consult it for pin assignments, supply limits, oscillator modes and programming pins. Note which device and package you have before measuring, because the 28-pin and 40-pin versions place signals on different pins.
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.
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