60hz clock

thiaguetz · Joined: 03 Feb 2004 Posts: 12 Location: Brazil

hi,

I want to make my PIC (16F628) oscillate at 60Hz and a timer that pulse every 0,5 second.

Anybody have an ideia on how to make this work?

Thanks!

valemike · Guest

The cheapest way to do it would to go off one winding of your transformer's secondary (i hope it's 24Vac or below), and put it in series with a somewhat big resistor, say 100Kohm, directly to RB0.

yeah it exceeds the ratings, but you do have internal clamping diodes to a diode drop below and above ground, and your current will be really limited by the resistor.

And since it's a schmitt trigger input, you'll have something like 6ms low and 10ms high, but your transitions will be a consistent 60Hz.

-Mike

Guest · Posted: Tue Mar 22, 2005 11:06 am

mmmm...

but, is there a way to do it using only clock settings on the software side?
And about the timer?

thanks

rwyoung · Joined: 12 Nov 2003 Posts: 563 Location: Lawrence, KS USA

Look for code in the Library / Code Snippit forum. I think it was Neutone that posted some very good no-error RTC code using the PIC's timers.

If it wasn't Neutone, then I appologize for not giving credit to the correct author.
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