Re: 20 Mhz 65816 CPU for IIgs

[supertimer@aol.com (Supertimer)]

martin lytz <mlytz@mindspring.com> wrote:

>I found the following part # at mitronics.com:
>W65C816PL-6
>They have 89 available.  I assume these are 6 MHz plcc parts.  Has anyone
>successfully overclocked these?  I have a request for quote out to them right
now.

These are an older design and can't be clocked much higher than 7Mhz
although a few can go to 10Mhz.  It depends on the chip.

You can tell chips of the newer design by the designation.  W65C816SPL-XX
where XX is the Mhz the chip is rated at and the "S" in SPL stands for
Sanyo, which redesigned the chip for WDC.  These chips are so good that
the Mhz ratings don't really mean much...many 8Mhz chips can go to
15Mhz and most of the 14Mhz units sent to CMD passed 20Mhz tests.

Actually, if you think about it, this design can probably go beyond 20Mhz.
It is just that no one has tested them above that speed.