Datasheet in PDF form (127 KB) for the AT89C52, an Atmel microcontroller from the 8051-compatible family with on-chip flash program memory. Technicians use it for the pinout, port functions, oscillator and reset connections, and the parallel programming timing needed to read or rewrite the part. It is useful when diagnosing a controller board that does not start, for checking the crystal pins and supply, and for confirming the exact package and suffix printed on the chip before ordering a replacement or loading firmware with a programmer.
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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