Giúp mình vấn đề Điều chế PWM

[manhhung_cdt08]

#include<16f877a.h>
#fuses hs,NOWDT,PUT
#use delay(clock=20000000)

main()
{
setup_timer_2(T2_DIV_BY_16,239,1);
setup_ccp1(CCP_PWM);
setup_ccp2(CCP_PWM);
set_pwm1_duty(64);
set_pwm2_duty(900);
while(1) {}
}