> > I am measuring clocks on my Money Money pcb but I have a problem with the tms5200
> > clock.
> >
> > The frequency counter measure a clock of 565khz instead of 640khz as stated in
> mame.
> > The problem is that there isn't a resonator near the tms5200. The clock pin is
> > connected to some resistors, capacitors and transistors. it is possible also that
> the
> > trace goes to the 3.58mhz osc but I can't follow anymore the traces.
> >
> > I believe the clock is made on the pcb with discrete components or discrete
> > components are used as divisors
> > In this case, what value should be put in mame?
>
> 640khz. Try measuring the ROMCLK pin of the chip, it should measure 160khz (it is the
> main clock / 4). trying to directly measure the clock at the OSC pin, given that
> money money uses the tms5200 in RC clock mode and not external clock mode, will
> always throw off the result, usually slowing down the clock speed significantly. This
> is true for all chips which use RC clocks.
The original message was from over two years ago... oh well, it'll help someone, I guess...
- Stiletto
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