Question about HPWM on a 28X1

[Andres Rodriguez]

Period is a variable/constant (0-255) which sets the PWM period
(period is the length of 1 on/off cycle i.e. the total mark:space time).
Does the 0-255 number represent milliseconds?

- Duty is a variable/constant (0-1023) which sets the PWM duty cycle.
(duty cycle is the mark or ‘on time’ )
What does this number represent?
Percent of the period?

I am trying to gradually increase the brightness of an LED and at the end jump to full brightness. Will this code work?

hpwm 0,0,%0001,100,100 ' start pwm
For Dty=100 to 700 Step 50
let pinsc=%00000000
pause 250  ' pause .25 s
let pinsc=%00001100
hpwmduty Dty ' set pwm duty
Next Dty
pause 100 ' pause .1 s
hpwmduty 1023 ' set pwm duty

pause 100 ' pause .1 s
hpwm off
let dirsc = %11111110
	goto Main:

 

[eclectic]

Marmitas.

Look at posts #2 and #4 in this thread.

http://www.picaxeforum.co.uk/showthread.php?t=1509&highlight=pwmout+250*+period

If you wish to vary the brightness on Leg 13 (pwm 2 / Out c2),
then this works

#Picaxe 28X1
symbol dty = w0

      Main:

For dty = 0 to 400

pwmout 2, 100, dty ; varies from 0 to 4 x period

pause 20 ; can be altered
next

	goto Main:

e

 

[Andres Rodriguez]

Thank you, it works great