Re: TransWarp & Zip GS upgrades

[CUTblakeney@home.com (Jeff Blakeney)]

On Sun, 26 Mar 2000 03:40:26 GMT, Marsha Jackson <menacechgo@aol.com>
wrote:

>Ahh, but a CPU designed to run at 14Mhz at 5 volts will therefore run fine at
>14Mhz with a lowly 5 volts.

Yes, that is correct.  I suppose I didn't mention the fact that you
don't need to touch the voltage at all if you are using the processor
at its rated speed or slower so I guess it is a good thing to state it
clearly rather than leave it up in the air.

>So, yes overclocking a 7Mhz to 8, or the 14Mhz to 20 might need a voltage
>boost, but 14Mhz on a 14 should be fine.
>(From WDC's website a W65C816S is designed to work from 1.2 to 6 volts.)
>http://www.wdesignc.com/ch816S.html

Something I didn't consider until after sending that last post is if
you are trying to overclock your processor other components on the
accelerator card might also need the extra voltage when operating at
the higher speeds.  My idea of just supplying the higher voltage to
the processor may not be enough for reliable operation depending on a
lot of factors.  In fact, going beyond a certain speed with a ZipGSX
accelerator requires that you change either the 74F00 or 74F02 IC (I
can't remember which at present) to a higher speed component like the
74HCT0x (again I can't remember the exact part number).

Another consideration when going to higher frequencies is how clean
the signal from the oscillator is when it gets to the processor.  If
it isn't clean enough, it may make the processor think that the clock
is either always high or always low.

Electronics can be such a fun field.  :-)

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