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carl_schell
- 3rd October 2003, 16:13
Hi al. I'm new to this forum, but I was impressed by the content I've read so far.

I am wondering if anyone has PBPro code for a frequency to voltage converter? I know I could use a F/V IC chip, but I have an application in mind in which I would like to use a 16F877 to do some basic data acquisition. I would be in debt to any help you could offer. Your new friend from Michigan in the US of A. Carl Schell

Melanie
- 3rd October 2003, 18:15
"Man can do anything if he will." - Maybe he should give it a go first...

I threw this example together in five minutes flat. There's a hundred different ways of accomplishing what you want... this is just one. Use as a teaching aid, learn and build from it. Study in conjunction with MEL's PBP manual and the 16F877's Datasheet section 8.3 (PWM Mode).

0-1023Hz input produces a correspondingly neatly linear 0-100% 10-bit PWM output. This PWM Output can be filtered (say via 10K Resistor first, then 1uF between that and Vss). You will generate your proportional voltage (0-5v in this case) across the Capacitor... buffer and scale it in a cheap op-amp for it to be useful and away you go.

PS. You owe me a holiday...

*smiles*
Melanie

carl_schell
- 3rd October 2003, 18:23
That puts me back on track to where I am going Thank you for the tutorial...I will study it and I will learn from it...If you're ever in the States...you've earned free room and board...

Thanks again Melanie ;

Carl