I'm prototyping a set of cycle lights where power comes from a dynamo to flash a 10w power led up front and in the rear.
The pic reads the freq from the dynamo so it can tell when its not going fast enough to light the 10w leds, and flashes 5mm leds instead from a pair of aa's, a 'stand light'.
The software so far works well, and switches from 10w leds to 5mm leds no problem, however I'm getting trouble with the 10f200 locking up and crashing at the point where the dynamo voltage goes above the battery voltage and the dynamo powers everything.
I have the usual decoupling caps and a smoothing cap on the o/p of the dynamo rectifier.
Seems like the pic doesnt like a slow rising vdd.
Is there a way I can get the chip to boot reliably without using the mclr pin?, the 10f200 doesnt have a brown out option, at the moment the pic is powered by the aa's only, thats not so good as when they go dead the whole system wont work.
The pic reads the freq from the dynamo so it can tell when its not going fast enough to light the 10w leds, and flashes 5mm leds instead from a pair of aa's, a 'stand light'.
The software so far works well, and switches from 10w leds to 5mm leds no problem, however I'm getting trouble with the 10f200 locking up and crashing at the point where the dynamo voltage goes above the battery voltage and the dynamo powers everything.
I have the usual decoupling caps and a smoothing cap on the o/p of the dynamo rectifier.
Seems like the pic doesnt like a slow rising vdd.
Is there a way I can get the chip to boot reliably without using the mclr pin?, the 10f200 doesnt have a brown out option, at the moment the pic is powered by the aa's only, thats not so good as when they go dead the whole system wont work.