CMOS 6502 variants (was Re: z80 timing... 6502 timing)

From: Eric Smith <eric_at_brouhaha.com>
Date: Sat Apr 17 20:13:02 1999

"Richard Erlacher" <edick_at_idcomm.com> wrote about CMOS 6502 variants:
> Yes, but there were three versions, at least, one being the Rockwell, one
> being the MOS-Technology , and the third was the Synertek/Western Design
> Center version. The VLSI Systems version was different from the Rockwell,
> but I don't know whether it was a completely different one or whether it
> fell in with one of the others. UMC made one, as did MITSUBISHI, however.
> I don't know where they fit in either. Do you?

As far as chips bearing the actual 65C02 or 65C12 designations, there were only
two types:

1) The straight WDC design, licensed by almost everyone, including UMC.

2) The Rockwell version, which was the WDC design with the addition of
    the bit instructions they had previously implemented in some
    of their NMOS parts.

Commodore also designed a CMOS 6502 core, but AFAIK it was never actually
marketed as a 65C02.

Mitsubishi makes a line of CMOS almost-6502 microcontrollers. They have
changed their part numbering system repeatedly. Some representative parts are
in the 3745x series. Most of their newer controllers are based on an
almost-65816 core.

Many ASIC vendors including VLSI have 6502 cores in their portfolio, but
they tend to be synthesized and don't share any common heritage.
Received on Sat Apr 17 1999 - 20:13:02 BST