Two different PWM frequency ranges

[benoitstjean]

PIC: 18F4620
Crystal: 16,384,000 MHz

The following code generates a PWM of exactly 128kHz 50% duty on PWM 1:

setup_timer_2( T2_DIV_BY_1, 31, 1 );
set_pwm1_duty( 16 );


PWM 1 = 16384000
-----------
1 x (31+1) x 4

PWM 1 = 16384000
-----------
128

PWM 1 = 128 000

How would I go about if I want my PWM 2 to be a totally different PWM frequency that requires a different calculation?

For instance, above, the function setup_timer_2( T2_DIV_BY_1, 31, 1 ); values 31 and T2_DIV_BY_1 gives me 128kHz.

But if I want PWM 2 to be 64kHz? I'd have to change 31 to 63.... Do I use a different timer?

I've used two PWM's before but both were the same frequency since they were for servos and the only thing I had to change were their individual duty cycles.

Now it's two different frequencies. I will check the manual but if someone know, please post it!

Thanks!

Ben

[asmboy]

The answer is for sure in the 4620 data sheet.
See table 15.1


You might try the 18f46K22
as it has 3 options in Timer see 14.3.3

The 46k22 may cost less $$ for more features as a bonus.