// led blink example Copyright (C) 2014 Diego Herranz

#define NO_BIT_DEFINES
#include <pic14regs.h>
#include <stdint.h> 

// Oscillator Selection bits (INTOSCIO oscillator: I/O function on RA6/OSC2/CLKOUT pin, I/O function on RA7/OSC1/CLKIN),
// disable watchdog,
// and DO NOT disable low voltage programming.
// The rest of fuses are left as default.
__code uint16_t __at (_CONFIG1) __configword = _FOSC_INTOSC & _CLKOUTEN_OFF & _WDTE_OFF & _BOREN_ON & _CP_OFF;

#define LED_PORT PORTCbits.RC5
#define LED_TRIS TRISCbits.TRISC5

// board layout:
// mosfets clockwise from power feed:
// RA5, RA4, RC2, RC3
// 'input' pin: RC5

// microsecond delay.
static inline void delay(uint8_t us)
{
  TMR1L = 0;
  while(TMR1L < us);
}
#define ADDTOUINT16(REG, LIT) __asm \
  BANKSEL REG \
  MOVLW LIT \
  ADDWF _##REG##L, F \
  CLRW \
  ADDWFC _##REG##H, F \
  __endasm
#define SUBFROMUINT16(REG, LIT) __asm \
  BANKSEL REG \
  MOVLW LIT \
  SUBWF _##REG##L, F \
  CLRW \
  SUBWFB _##REG##H, F \
  __endasm
#define PPSO_PWM1 3
void main(void)
{
  OSCCON = 0xf0;
  TRISC = 0;
  T1CON = 0x31; // timer1 at 1 mhz, so 1us
  ANSELA = 0;
  TRISA = 0;
  //SLRCONC = 0;
  LED_PORT = 0;
    PWM1CLKCON = 0x00;  // From Fosc w/o prescaler
    PWM1PRH = PWM1PRL = 0xFF; // period: 32 mhz / 65535 = 488 Hz
    PWM1PH     = 0;
    PWM1DCH = PWM1DCL = 0;
    PWM1OF     = 0;
    

    PWM1INTE   = 0x00;  // no interrupts enabled
    PWM1INTF   = 0x00;  // clear interrupt flag
    PWM1LDCON  = 0x80;  // load armed
    PWM1OFCON  = 0x00;  // independent run mode
    PWM1CON    = 0x80;  // enable, standard PWM mode, active high output

    RC5PPS = PPSO_PWM1;


    while(1) {
      while (PWM1DCL < 0xFF || PWM1DCH < 0xFE) {
        ADDTOUINT16(PWM1DC, 1);
          
        PWMLD = 1;
        delay(50);
      }
      while (PWM1DCL > 0 || PWM1DCH > 0) {
        SUBFROMUINT16(PWM1DC, 1);
        PWMLD = 1;
        delay(50);
      }
    }
}