16f877 what is the problem ?

Discussion in 'Embedded Systems and Microcontrollers' started by B&H, Apr 27, 2009.

  1. B&H

    Thread Starter New Member

    Apr 27, 2009
    Hello !

    I have enabled WDT , and clear it all the time with "CLRWDT".
    I wrote an Interrupt service routine (ISR - short). That ISR calls other two subroutines. Between these two subroutines there is assembly command "CLRWDT".

    If I call just routine no 1 (not call to routine no 2) - no problem, everything is working as I want .
    If I call just routine no 2 (not call to routine no 1) - again, it is all right.
    But if I call routine no 1, and after that I call routine no 2 problem occurs,and that is ISR stops working and I get in the main routine.

    What is the mater ? I can t get it? It gets me crazy for days :mad:

    Thank you :).

    Is there anyone to tell me what is the mater