Dear Sirs, I've developed a product on basis of PIC16F442. On some conditions my unit goes to the SLEEP mode and wake up from the SLEEP on WDT time-out or on an interrupt. The postscaler,I've taken, is 64, giving us 64 * 18msec = 1.152sec. I tested it with MPLAB ICE-2000 and found everything is OK. But then I burned the real chip(I have only PIC16F452) and found that the WDT time-out is 18mses instead of 1sec as desired, meaning the postscaler does not work. I don't know how to eat it. I will be very grateful for any idea or suggestion. Thank you in advance and best regards.
PIC16F452 WDT time-out problem
Started by ●March 22, 2004
Reply by ●March 22, 20042004-03-22
>I've developed a product on basis of PIC16F442. On some conditions my >unit goes to the SLEEP mode and wake up from the SLEEP on WDT time-out >or on an interrupt. The postscaler,I've taken, is 64, giving us 64 * >18msec = 1.152sec. >I tested it with MPLAB ICE-2000 and found everything is OK. But then I >burned the real chip(I have only PIC16F452) and found that the WDT >time-out is 18mses instead of 1sec as desired, meaning the postscaler >does not work. I don't know how to eat it. >I will be very grateful for any idea or suggestion.I assume you mean PIC18F442/452. You should make sure the configuration bits are set using assembler directives in your source code. I believe these override the configuration bits settings of the MPLAB IDE.