internal oscillator

derya · Joined: 12 Jan 2005 Posts: 4

As I know, some PIC models have internal oscillator circuit and no need to assemble any external oscillator. Such models run with 4MHz frequency in general. Which models of PIC has internal oscillator? Is PIC16F648A has? If it has;Could you give me the example code?

Mark · Joined: 07 Sep 2003 Posts: 2838 Location: Atlanta, GA

Don't be lazy, go here:

www.microchip.com

SherpaDoug · Joined: 07 Sep 2003 Posts: 1640 Location: Cape Cod Mass USA

Beware that most of the internal oscillators have poor accuracy and may not even be good enough for reliable serial communication. But if you are just making a talking Teddy bear they may be fine.
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Mark · Joined: 07 Sep 2003 Posts: 2838 Location: Atlanta, GA

So far this poster wanted to generate a 1MHz PWM. If that is still their intention, it is not going to happen and 4MHz (not with a 25% duty cycle).

derya · Joined: 12 Jan 2005 Posts: 4

Hi,

I have achieved to get 1MHz PWM signal with 1/4 duty cycle.
I used 20MHz oscillator and parameters are as following;

setup_timer_2(4, 4, 1);
set_pwm1_duty(1);

Thanks...

regall · Joined: 15 Jan 2005 Posts: 6 Location: Turkey

Guest · Posted: Tue Jan 18, 2005 1:14 am