Need help to shut off comparators for 16f688

[jessey]

Hello,

I'm trying to shut off the comparators on my 16f688 and can't seem to accomplish it, as a result I can't get RA0 or RA1 to function as expected. When I use CMCON0 = 7 or CMCON0 = %00000111 and try to compile, I get an error message saying there is a syntax error.

I'm using PicBasic Pro Ver 2.45, MPASM Ver 3.60 with MicroCode Studio 2.1.0.7 and EPIC Version 2.46 beta programmer with a PIC16F688-20/P.

Would anyone have any suggestions on why it won't compile? I looked at the data sheet and CMCON0 = %00000111 is a valid command and I've also seen this used in code examples while looking in the archives.

Any help would be very much appreciated.

Thanks
jessey

[HenrikOlsson]

Hi Jessy,

Do you have the right chip selected in MicroCodeStudio?

I believe you also need to clear the corresponding bits in the ANSEL register to make the pins digital.

/Henrik Olsson.

[jessey]

Hi Henrik,

Thanks for your reply. Yes I have selected the 16f688 in the MicroCode Studio drop down list and I'm also using ANSEL = %00000000.

Any other ideas?

Thanks
jessey

[savnik]

When I use CMCON0 = 7 or CMCON0 = %00000111 and try to compile

use : CMCON = 7

[jessey]

Hi savnik,

When I try and compile using CMCON = 7 I get an error saying 'Symbol not previously defined (CMCON)'. I checked the data sheet and the only reference it makes to CMCON is in a, Modified Comparator C1 Output Block Diagram in figure 7-4 and 7-5.

Thanks
jessey

[Darrel Taylor]

Hi Jessey,

I have both PBP 2.45 and 2.46

In 2.45 I get the same error you described. With 2.46 I don't.

But without upgrading, you might try

POKE $19, 7

HTH,

[jessey]

Hi Darrel,

That's great, it works like a charm now. I'll have to upgrade to the newest version. I'm in your debt once again.

Thanks a million
jessey

[Darrel Taylor]

No need to be in debt.