pot controlled pwm -- help

[sayzer]

Try the attached PWM filter.
Play with the driver resistor and the load resistor to catch a nice signal out.

If you already have a signal amplifier, the NPN transistor may not be necessary.

[Acetronics2]

Hi, Sayzer

PWM is intended to know what you apply to your load, your design is very very very very far from giving a known output ... it's more an ON/OFF output than anything else.

Alain

[milestag]

I don't really care for the HPWM command. I think it's easier to manually set the registers. This is a conversion from part of my code that may work for you to at least get the PWM working.

This is for an 8MHz oscillator (on a 18F2525, so double check register names):

T2CON = 4 'Timer2 = ON; Prescale = 1:1
PR2 = 200 '(period) this should give you should give you about 10KHz
CCPR1L = 100 '(duty cycle) 100 should be close to 50%, 20 is about 10%, etc

To turn PWM ON:
CCP1CON = 12

To turn PWM OFF:
CCP1CON = 0

[sayzer]

Hi Acetronics,

PWM filter is not something I created through my output port; it is what picbasic pro recommends.
If you check the manual or help files, you will find this filter as a solution to scarry pwm out. Still, it is optional.

If you know something else, pls share it with us so that we can learn. Also, PWM is already an on/off state with different intervals on ON mode, on OFF mode etc. and this is called "modulation".

[Acetronics2]

Hi, sayzer

As you're asking, it's a pleasure ...

Just insert a resistor between your Emitter and ground, and the transistor collector current will simply follow linearly ( w. a little offset due to Vbe ...) the PWM value ...
An U/I converter w/ OpAmp could wipe off this offset, if needed ...

No, no, don't send flowers ....

Alain