Pic resetting

[keithdoxey]

I seem to remember reading in one of my magazines many years ago that the 555 momentarily draws a lot of current from the supply when changing its output state. Try a large decoupling capacitor close to the 555 (100uF or higher)

I also seem to remember that the CMOS version 7555 is much more gentle on the power supply.

[malc-c]

Thanks Keith, I'll give that a go too

[Archangel]

You might also disable brown out detection on your pic config fuses too.
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