INTOSC madness

[PerranOak]

I'm using a 12F683 and have been setting FOSC = INTOSCIO and everything is fine.

Then I changed things (extra info included, the only other thing I changed was the freq from 4MHz to 1MHz):

Code: [Select]

#include <xc.h>
#include <stdio.h>
#include <stdlib.h>
#define _XTAL_FREQ 1000000

#pragma config FOSC = INTOSC
This is so I can output the clock.

Now I get this error:
683_Shift_Reg.c:14:: error: (1363) unknown configuration setting/register (FOSC = INTOSC) used

Could I please have a clue as to where to look for the right command, cheers.

[Doctorandus_P]

Set _XTAL_FREQ back to 4MHz?


Or:
Use your IDE to seach through the "library" code & header files for "_XTAL_FREQ" and how it is used.
It's likely that dependent on different ranges of values different settings are chosen, and the settings for 1MHz apparently do not agree with FOSC = INTOSC.

You can of course also search for those macro names.

[cv007]

Look in pic/dat/cfgdata/12f683.cfgdata-

INTOSCCLK is probably what you are looking for (or a couple other name variations).

[hexreader]

cv007 is of course correct with INTOSCCLK

The way I would have found this is:

From the MPLABX IDE Select:

 - Production
 -       Set Configuration Bits
 -            to the right of field FOSC select the down arrow
 -                choose from the drop-down list

Either "Generate Source Code To Output" and copy/paste the resulting output to your code window, or manually edit as you prefer

[jpanhalt]

Probably I misunderstand.  Do you want intosc out using the internal oscillator or a crystal?

The setting for 1MHz is b'0100xxxx' in the OSCCON register if using the internal oscillator.  If using a crystal, it doesn't matter.  Then in configuration, you need to define INTOSCIO or INTOSC and so forth.

[PerranOak]

Thank you all very much.

I wanted to output the internal oscillator. It wasn't the freq that was the problem, thanks, see below.

Thank you, the command: INTOSCCLK worked perfectly.

I had completely forgotten about the "Set Config Bits" pull-downs. I generally copy all that stuff from previous projects and alter the things I need to, hence my INTOSC error. I will  use that in future, thank you.

Interestingly, I looked in the file, 12f683.cfgdata and found:
CVALUE:5:INTOSCCLK,_INTOSC,_INTRC_OSC_CLKOUT:INTOSC oscillator: CLKOUT function on RA4/OSC2/CLKOUT pin, I/O function on RA5/OSC1/CLKIN

Of course, INTOSCCLK worked but, for fun, I tried: _INTOSC.
This output the clock at the expected freq but instead of being a nice, sharp square wave, it's edges were curved like you get when there is lots of capacitance around.
When I went back to INTOSCCLK it was the nice, sharp wave again.

Not a problem, just interesting.