PWM fluctuates on PIC18252

[gringo332]

Thanks for the replies! I will look into it and let yall know what happens. Only thing is I don't remember this being a problem when I ran this same code on a 16f876.

[skimask]

DEFINE OSC 20
DEFINE LOADER_USED 1 ;bootloader
main

x var byte
counter var byte

TRISB.1 = 0
TRISa.2 = 0
TRISB.2 = 0
high porta.2
low portb.2
pwm portb.1,150,200
counter = counter + 1

if counter > 127 then 'if counter is less than 128 turn led on
low porta.2 'if counter if greater than 127 turn led off
else
high porta.2
endif

goto main
end

Thanks for the replies! I will look into it and let yall know what happens. Only thing is I don't remember this being a problem when I ran this same code on a 16f876.

If I was going to do the same thing and use the 'software' PWM command, I might change your original code to what I put above, or maybe use a word value instead of a byte and change the cutoff point to 32767, or reset the counter if it hits 100, or 10000, or whatever.

[gringo332]

I see what was causing the motor to rev up. If you loop the PWM signal but if there is a PAUSE (i.e flashing an LED) before looping back this causes it to act this way. I think the motor responds this way when it is turned off. But if you loop back quickly the Pulse seems continuous with no hiccups. Yall are right, that I will probably have to use hardware PWM because I would be taking input from Infrared and doing some calculations before looping back.

Thanks for the suggestion again guys!