Writing the Config1h Register on the PIC18F2580

guest · Guest

I am attempting to write 0110 to the Fosc3:Fosc0 bits in the Config1h register of my PIC18F2580 to enable external crystal PLL mode. In the manual on page 345 it details how to do this, but I am not completely sure how to directly write registers outside of using the #byte directive (maybe this is how I need to do it?). Setting these bits requires a special procedure similar to "programming the flash memory" according to the manual so I was wondering if someone had done this before and could give some guidance (and maybe a code snippet). Anyone able to give me some tips?

PCM programmer · Joined: 06 Sep 2003 Posts: 21708

Use the #fuses statement. Look near the top of the 18F2580.H file
for a list of settings that you can use.

Example:

Bryan · Joined: 23 Apr 2005 Posts: 73

Is H4 fuse the HSPLL setting as described in the data sheet? Sorry, I accidentally posted as guest before, but the first post was mine as well. I still haven't been able to find a listing of what each fuse means - is this listed somewhere?

PCM programmer · Joined: 06 Sep 2003 Posts: 21708

Yes, H4 is the same as HSPLL for that PIC.

Here's the thread on #fuses.
http://www.ccsinfo.com/forum/viewtopic.php?t=24336
Humberto shows a list of fuses with explanations. I'm not sure where
that comes from. I don't know if he created it or if PCWH created it.

I do know that if you go to the View menu in the IDE and select the
"Valid Fuses" menu, you'll get a pop-up window. Then select your PIC
in the drop-down box, and you'll see a list of fuses with an explanation
next to each one. (This is for PCWH vs. 3.249. I looked at the demo).

ckielstra · Joined: 18 Mar 2004 Posts: 3680 Location: The Netherlands