16F877 resets itself?

sraiderk · Joined: 09 Feb 2005 Posts: 48

I use the 16f877 with version 3.212 . I use timer0,1,2 interrupts and also
rs232 receive interrupts. Not always, But sometimes pic resets itself. Is it normal? what can be the reason for this. My code is really big. it makes multifunctions. I hope this error coming from rs232. Please looking this view. Thanks a lot up to now. Byee...

Mark · Joined: 07 Sep 2003 Posts: 2838 Location: Atlanta, GA

sraiderk · Joined: 09 Feb 2005 Posts: 48

Thanks Mark for your reply. I accept your idea. I use the fuse like the following.

#fuses HS, NOPROTECT, BROWNOUT,LVP,WRT

My question I don't know the meaning in using

LVP:Low Voltage Programming enable bit ?

sraiderk · Joined: 09 Feb 2005 Posts: 48

Thanks Mark for your reply. I accept your idea. I use the fuse like the following.

#fuses HS, NOPROTECT, BROWNOUT,LVP,WRT

My question I don't know the meaning in using

LVP:Low Voltage Programming enable bit ?

Mark · Joined: 07 Sep 2003 Posts: 2838 Location: Atlanta, GA

It is doubtful then you are using it. You need to change LVP to NOLVP. If you don't, a change on the LVP pin will cause problems.

newguy · Joined: 24 Jun 2004 Posts: 1903

Also check the C/Asm list file. Near the top, the compiler will tell you how many stack locations your program will use. The 16 series chips only have an 8 level stack. If your program is trying to use more than 8 locations, it will hang and eventually the watchdog will reset the pic. This may be the cause of what you're seeing.