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Replace rare/expensive/unreliable MOS CPUs
6510 (C64) (8500 is same as 6510)
6510T (1551 floppy drive)
8501 (C16, C116, Plus/4) (7501 is same as 8501)
8502 (C128)

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If you want one, check my store for stock: (

The above four CPUs have the same dies I believe, with just different internal pads exposed to the DIP-40 pins.
It's a standard 6502 die, with an added 8-bit bidirectional I/O port, tri-state bus buffers, and an AEC latch enable for 8501 mode.

This device uses a standard 6502 CPU, and implements the extra functions using discrete logic - no programmable parts.
Standard 6502 CPUs are abundant and cheap, and produced by many manufacturers (Rockwell, UMC, Synertek, MOS, etc).

You can use a 65C02 or W65C02, but this is untested, and will cause compatibility issues with some software at the least, or not work at the worst.
If using a WDC W65C02, you must cut jumper W.

Monotech PCs - MOS CPU Replacer

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