// PIC18F14K50 in C - Versione 0.2 - Novembre 2010
// Copyright (c) 2010 VincenzoV.net
// Creative Commons | Attribuzione-Condividi allo stesso modo 3.0 Unported.
// Creative Commons | Attribution-Share Alike 3.0 Unported
// https://www.vincenzov.net/tutorial/elettronica-di-base/PIC18F14K50

// Hardware PWM

#include <p18f14k50.h>
#include <delays.h>
#include <timers.h>
#include <pwm.h>

#pragma config FOSC = IRCCLKOUT  // Internal RC oscillator (F/4 to OSC2 - pin 3) 
#pragma config WDTEN = OFF       // Watchdog disabled
#pragma config LVP = OFF         // Disable Low Voltage Programming
#pragma config MCLRE = OFF       // Disable MCLR

#define CLOCK 16      // Main clock [MHz]
#define PWM_T 50      // PWM period [us]
#define DC 40         // PWM DC% (0-100)

void main (void)
{unsigned int period;   // PWM period 
 unsigned int Ton;      // PWM Ton

 if (CLOCK == 16) OSCCON = 0x70; // Set internal clock to 16 MHz - test other frequancy required...

 OpenTimer2( TIMER_INT_OFF & T2_PS_1_1 & T2_POST_1_1);
 
 period = ((unsigned int)CLOCK * PWM_T) / 4 - 1; // Only if T2_PS_1_1 (prescaler2 = 1) - 16 bit integer, unsigned
 if (period > 255) period = 255;                 // Timer2 is has only 8 bit
 
 OpenPWM1(period);                               // Set PWM period
 SetOutputPWM1 (SINGLE_OUT, PWM_MODE_1);

 Ton = (unsigned long)CLOCK * PWM_T * DC / 100; // 32 bit integer, unsigned
 if (Ton > 1023) Ton = 1023;                    // Only 10 bit allowed
 
 SetDCPWM1 (Ton); 

 while (1);  // Endless loop
   
}