38Khz Modulator

[languer]

You can see another example on the following two links:
http://www.electro-tech-online.com/c...nications.html
http://www.electro-tech-online.com/b...-test-bed.html

[Gord11]

Ok,

I understood the electronics, but have have been looking at the datasheet for the 12F683.

I am sure this is going to end up being a simple answer, but i have been looking at the duty cycle settings for the PWM, it's just not making
sense to me!

I have seem other posts, setting the CLPR1L to 13, which would be half (50%) of the 26uS period. But when i look at the calculation for the duty cycle in the
datasheet i am not understanding. If you put 13 in the CLPR1L (ie. 1101), does this then add to CCP1CON 5:4, (i.e.00) to make 1101 00 = 52 - then 52*0.25*1=13uS........

(0.25 Tosc & 1 prescaler).

Also, why does it say in the datasheet, 10bit PWM. Max 20Khz?

As you can tell i am still at the very start of understanding PIC programming.

Gordon,,