Mike Harrison wrote: > A couple of alternative approaches, on the basis that if a LED's=20 > electrical characteristics are > right, it's highly unlikely that it isn't lighting: > a) Configure the circuit so the LED forward voltage could be measured=20 > using a spare ADC pin - this > could also discriminate incorrect colours due to different Vf Sorry, no spare ADC pins. > b) Measure the current draw of the device while the LEDs are operated in = a=20 > known sequence - this > would catch opens and shorts. This sounds like a good idea, especially since we're measuring the current= =20 anyway. Unfortunately, one of the LEDs is wired permanently ("Power") and=20 one is driven by a third party module (it blinks). It may still work,=20 though. Vitaliy=20 --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .