how to generate a PWM(20KHz) for 0 to 5V i/P using PIC16F72

[codekuru]

pwm 20khz

Hi,
my requirement is to generate a PWM wave(20KHz). i am using PIC16f72 Micro controller. i have 0-5V Variable Input. i have to generate a waveform corresponding to tht input signal.tht wave form need to have 50% Duty Cycle.
Plz help me in this problem. if anybody can giv a sample pgm for this will help me very much.
For programming which language is suitable in this condition, C / ASM?
i hope tht many of you can help me very much.
thanks & regards,
sarin

 

[IanP]

pwm 20 khz

If I may suggest something, swap horses and use PICAXE microcontroller as it has build-in PWM function and a number bewteen 0 and 1023 can be used to generate PWM between 0 and 100% ..
Here is an example:


Regards,
IanP

 

[alec82]

generate 12 to 5v

hi
u can use ccs c compiler for this target
here code for your requirement:

#include <16F72.h>
#use delay(clock=4000000)
#fuses NOWDT,XT, NOPROTECT
int value;

main()
{
   setup_adc_ports( ALL_ANALOG );
   setup_adc(ADC_CLOCK_INTERNAL );
   setup_timer_2 ( T2_DIV_BY_4, value, 2);
   set_adc_channel( 0 );
   setup_ccp1(CCP_pwm);
   while(true)
   {
      delay_ms(100);
      value = read_adc();
      setup_timer_2 ( T2_DIV_BY_16, value, 2);
   }
}