I agree 100%. The microprocessors and peripheral chips don't have Schmitt triggers to shape the external reset, so it needs to be a well formed reset that hold the system in reset at least a few clock cycles more than the specifications, to allow for aging of the components. I prefer to hold it in reset three to five times the specified clock cycles, just to be sure.
-- You can\'t have a sense of humor, if you have no sense!
If you have an oscillator that has to start (and stabilize), you'd better wait for it too. ;-)
These used an external chroma source, and the CPU clock was divided down from that. There was an internal fail safe source, but the unit was useless without external sync & clock signals.
-- You can\'t have a sense of humor, if you have no sense!
Perhaps this is what you are seeking:
Don...
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I was speaking in the general sense. R-C resets suck because they cannot be guaranteed to work.
Microchip and Dallas both make TO-92 packaged 3 terminal reset circuits. Like the DS1233. They work well, allow the use of a push button in parallel with the reset for manual resetting and you can specify the voltage range you want it to reset at.
Jim
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