12f629 freq divider?

[skimask]

Hi,
how I can use SSPWM (Slow Speed PWM) code with 12F675?

You can't.
Not enough on chip register space for the variables required.

[Darrel Taylor]

Where do you come up with your answers skimask?

8-Ball?
Dart board?

Of course you can run it on a 12F675.
Just comment out the wsave1 wsave2 and wsave3 variables, since the 12F675 doesn't have GP RAM in those banks.
<br>

[skimask]

Where do you come up with your answers skimask?
8-Ball?
Dart board?
Of course you can run it on a 12F675.
Just comment out the wsave1 wsave2 and wsave3 variables, since the 12F675 doesn't have GP RAM in those banks.
<br>

Both of them...I assign points to each answer, then take the average point out of 7 tries.
Fine, it can be run on a 12F675. I thought there was only 24 bytes ram on a '675.
The average Joe isn't going to know to comment out those wsave variables until the compiler/assembler whines about it. Then the average Joe isn't going to know what 'Unable to fit variable wsave3' means after hitting F9. Then what is the average Joe going to do? Ask questions of course. A comment in the sspwm.inc file would fix that.
I haven't tried it on anything less than a 16F628A. I'll play with it this weekend on an 'F629 and see what happens.

[Darrel Taylor]

I thought there was only 24 bytes ram on a '675.

64, but it won't matter much.
SSPWM uses ASM interrupts. So the issue of saving all the PBP system vars doesn't apply.

A comment in the sspwm.inc file would fix that.

Or maybe a note to use the current version.

SPWM_INT - Multiple Software PWM
http://www.darreltaylor.com/DT_INTS-14/SPWM.html
<br>

[skimask]

64, but it won't matter much.

That's what I get when I get my 10Fxxx's and 12Fxxx's corn-fuzzed...

SPWM_INT - Multiple Software PWM

Well then that's the one I'm going to play with some more...

[rmteo]

Ski, if you get the 24-bit stuff, here is a what a PIC24 will do in this kind of situation:

1. Hardware PWM from 30Hz to 500KHz+.
2. Up to 16-bit duty cycle resolution at lower frequencies.
3. Up to 5 independent hardware PWM's.
4. 0% processor overhead.
5. Virtually no coding - except to set up registers.

All this from a single $2, 28-pin device.