A 5.14 MB PDF datasheet covering the Microchip PIC18Cxx2 group of microcontrollers, where xx stands for several family members sharing one document. The C in the part number denotes EPROM or OTP program memory rather than flash, which matters if you plan to replace or reprogram a chip. Use the document to identify pin functions, supply ranges, oscillator options and programming requirements. Read the part marking on the board carefully and match it to the correct device table, since memory sizes differ between members.
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