pic axe08M hanging up

I have three switch inputs to an 08M, two LED outputs, one a standard LED and the other an infra-red LED.
The led's flash when an input is pressed. One flash for one button, 2 flashes for another and 3 flashes for the 3rd button. infrared led is flashed using infraout command.
Problem: two buttons work as expected, but the third button causes the output leds to remain lit for approx 5 seconds, the picaxe appears to hang up, then reset again? Any ideas on why the pic is doing this?
all code has been tested on a duplicate board & simulated fine.
all pull-up resistors in place and voltage tested with a multimeter fine.
have checked many times for a wiring short, but nothing visible, also checked with a meter.
How does the pic-axe enter a reset state? the chip seems to resume normal operation after a few seconds, but accepts no inputs form the two good switches during this hang-up/reset state.


Technical Support
Staff member
For an 08M a reset would be through power loss or brownout, or a high signal seen on the Serial In line - I forgot to mention pulling that low or ensuring the 10K/22K is in place.

Drawing high or too much current through an I/O line, external electrical noise and ESD could cause a reset. Decoupling capacitors across the power rails will help keep down effects of noise. Operating outside normal voltage specs could cause odd behaviour.

Switch PICAXE's between boards and see if the problem moves with the PICAXE or stays with the board.