I am trying to generate a quasi sine wave at 60 hz. The program runs but the waveform is upside down. I could change the circuit to accept the upside down wave, but I would like to know what is going on. This is my simple code:
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 = %111111 '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
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

If I change all highs to lows and all lows to high in the loop, I get the idenical same hex code. I would expect that
high gpio.0
highgpio.1
start:
low gpio.1
would give a different hex code than
high gpio.0
high gpio.1
start:
high gpio.1

Russ