Microchip PIC16F62x datasheet, a 4.09 MB PDF covering the 18-pin flash microcontroller family that includes parts such as the PIC16F627 and PIC16F628. The x placeholder in the name means several members share this document. It describes pinouts, internal oscillator, comparators, USART and electrical characteristics. For repair work, consult it to check power and reset pins and to set the correct configuration when reprogramming, making sure your programmer supports the exact variant on the board.
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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The standard format for schematics, block diagrams, power-sequence charts and service manuals.