Melanie where are you?

[Russ Kincaid]

I am beating my head against a wall trying to figure out why this program makes GPIO.0 output high for 4ms and low for 12ms. Also, GPIO.1 output is high for 8ms and low for 8ms. I would expect GPIO.1 to be low for 4ms and high for 12ms. GPIO.0 should be high all the time.

REM DEVICE = 12F675 '12F629 CAN ALSO BE USED
REM USE INTERNAL OSCILLATOR, OUTPUT IS ON GP4 (PIN 3)
REM CONFIGURATION: INTOSC CLOCKOUT, WDT DISABLED, PWR UP ENABLED,
'MCLR = OUTPUT PIN, BROWN OUT DISABLED, NO PROTECTION
REM 60 HZ OUTPUT IS ON PINS 7 AND 6
REM OSCILLATOR CHOICE: USE 101, INTOSC, CLKOUT
OPTION_REG.5 = 0 'OTHERWISE GPIO.2 IS AN INPUT
TRISIO = 0 'SETS ALL PORTS TO OUTPUT
ANSEL = 0 'SETS ALL DIGITAL MODE
DEFINE OSCCAL_1K 1 'FOR OSCILLATOR CALIBRATION, DON'T KNOW HOW IT WORKS

high GPIO.0 'INITIAL CONDITIONS
high GPIO.1

START:
low GPIO.1
PAUSEUS 4168 ' ON TIME
high GPIO.1
PAUSEUS 4167 'DEAD TIME, BOTH high
REM low GPIO.0 'SETS PIN 7 low
PAUSEus 4168 'FOR 4.168 MILLISECONDS
high GPIO.0
PAUSEUS 4167 'DEAD TIME

GOTO START '60 HZ FREQUENCY

END

[mister_e]

Where's the CMCON setting?

[Darrel Taylor]

Yeah, I would've asked for the pretty girl first too.

But I think mister_e nailed it. CMCON
<br>

[Russ Kincaid]

Hay, thanks for the replies. If ANSEL = 0, I don't see why CMCON setting would make any difference. I tried CMCON = 0, no difference. Is there some other setting that would make sense?

[paul borgmeier]

CMCON = 7
(7 = all digital, 0 = one of the analog modes)

[JohnH]

Try setting CMCON=7. Bits 0,1,2 high in CMCON=Comparator off. GP0 and GP1 pins are multiplexed to the comparator inputs. Something to try...

--John

[JohnH]

Paul beat me to it... hope it works.