A 32-bit successor to 6502: the MCS65E4 (1982 design doc)

I wrote up some thoughts on the 65e4 over on the 6502 forum. One commenter, John West, says: “That’s what the future looked like in 1982, if you weren’t paying close attention to the more researchy end of development.”


That was a good discussion (once it moved on from the quality of the scan).

While it was certainly the wrong thing to do at the time, with a transistor budget similar to a Zen 2 it could actually be a competitive processor today.

Except for one phrase saying it could run 6502 there is nothing in the document giving a hint of how it might do so. I found it interesting that they had not yet assigned op codes in this “final” version of the text. Given how few instructions it has and how structured the bits in the first byte are I would think this assignment would be far simpler than for most processors.

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