check LED before tearing out hair.

Yesterday I spent 2 hours with the SIMPLEST of code, and couldn't get an LED to blink on and off properly. Instead of blinking on for 1 second, then off for one second, it would blink on and off twice in one second, then off for 1 full second. I used decoupling cap, checked my supply voltage, checked my OSCCON settings, the oscillator configuration settings, the whole nine yards. Recompiled, reprogrammed, refrustrated.

Finally, I discovered that I had grabbed a FLASHING LED out of my parts bin.

Conclusion: Don't rule out something EXTERNAL.

----------Picster------------

That IS funny. I know it wasn't at the time though. Last week I was driven absolutely crazy. I kept making change after change to a program but nothing changed! Turns out the program didn't overwrite the previous hex file when it was recompiled. Solution: reboot the computer. Everything back to normal. - Peter

Thanks for the chuckle. However, I think your rule should be revised to:

Conclusion: Don't rule out ANYTHING