> > That may take a lot to get that idea to work.  Lots of variation in
> > that process.
>
> If I did the following:
>
> 1. Got away from the xtal, and stayed with the reduced clock
> usually available on pin 20 or 22 of the eprom,
>
> 2. got away from powerup and just used watchdog resets

Well, actually, you can't get away from power-up reset when you turn the
power on.  Because many micros have dynamic cells inside instead of static.
The charge pump for biasing them has to start operating and the cells have
to be initialized.  When you first turn the power on, you're dealing with
the Analog part of the digital device.

> Then I would have a high on the reduced cpu clock ( 'E' or pin
> 64 on the HD6303XP & HD6303YP) until the xtal was set going. The time
> between end of reset and first clock cycle would be immaterial. The
> start of my scan would be the start of the first read cycle.
>
> What I really wanted to avoid was having to stick a clip on the eprom
> and trap an opening read at a low address to get the start signal, and
> processing also to get a stop.

That's the only reliable way that I can think of to do it.  That first read
is the signal that says the processor is up and running. ??

-- 
Author: Dave Baldwin
  INET: [EMAIL PROTECTED]

Fat City Hosting, San Diego, California -- http://www.fatcity.com
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