I have seen similar thing once in my program. I figured that had to do with my interrupt routine. I used it to do the timing and other stuffs; perhaps it got too long trying to do too much at the same time. I don't know if that was the cause, but after I shortened my interrupt routine it didn't happen again. Try to see if that helps you. Tony Pan ----- Original Message ----- From: Simon Ethier To: Sent: Wednesday, March 28, 2001 6:25 PM Subject: [PIC]: Flashing a LED I have a small program to flash a led, when I program it in the PIC16F84A with my P16PRO programmer, the LED is flashing BUT, it ain't flashing as it is supposed to. Instead of bein "on" for 500ms (or so) and then shut off for another 500ms(or so), and then start this forever, the LED do this : it goes on for about 500ms, then shut off for another 500ms, then in a 500ms laps time it does this : it goes on for I'd say150ms, goes off for 150ms, then goes on for 150ms. After this, it starts again : goes off for 500ms, goes on for 150ms, off 150ms, etc... So it seems the time it is supposed to be "on" for 500ms, in that period of time it goes on, off, on Anyone has an explanation for this ? (I hope your were able to figure out what it is doing .... hehe) thanks --- Simon Ethier -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads