Thanks for that but I thought I could drag from memory that someone wrote that (on the nanowatt?) PIC's you should use an external pull-up on MCLR and not use the internal. I dunno why. I could be wrong in my recollection - usually am. Can anyone shed more light?
resets.
On'
supplies
Nice circuit Fred. The input CR idea can adjust to give any hold-off time wanted. I do similar when I've any CMOS inverters knocking about. For a supply with switch bounce as the defined problem I'd be inclined just to add a 10u at the 15k-33k junction on my original circuit. With say low loads, then both circuits 'snap' on with similar times, say a couple of mS. But ... I'd suggest the first circuit has the benefit of simplicity, in that it doesn't need a seperate 5V regulator or a floating power supply. regards john
There's no problem with the internal MCLR action . It's just that when it's programmed 'out' then the PIC reset action falls back to a second (less secure)level, of being reliant on the internal power-on-timer. For this timer circuitry to do it's job it can only assume the PIC power supply is OK. If the PIC supply is still thrashing about while the timer circuitry is trying to count, then counting problems turn up. It's one of those "who guards the guardians" type hardware conundrums that the Microchip software people can't seem to grasp. regrads john
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