PWM signal from a pic

[rob_croxford]

Hi all,

I have recently designed a program for the PIC12f683. This program takes an input voltage of 0-5VDC and creates a PWM signal on the output. (0V = 0% duty, 5V = 100% duty) so far i have managed to get the output at arround 1000Hz.

My questions are:

Is it possible to get a low frequency PWM signal out of a pic??
Is it possible to use an external clock to create this frequency??


Any help is greatly appreciated.

 

[rob_croxford]

I didnt realise the PIC12F683 had various oscilator frequencies (125KHz - 8MHz). i have set it at a lower one now

 

[Shahrul]

With 20MHz Crystal, minimum PWM frequency can generate is 1250Hz. See example to use analog input 0-5V to vary Frequency and Duty Cycle http://shahrulnizam.com/pic-lesson-pwm-module/

To generate frequency lower than that, you can use timer interrupt. See example to generate 50Hz PWM http://shahrulnizam.com/pic-lesson-servo-motor/