Subversion Repositories Code-Repo

Rev

Rev 272 | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
163 Kevin 1 
#include <xc.h>
2 
#include "defines.h"
3 
#include "base_PWM.h"
4 
 
5 
void PWM_Init() {
6 
    // Output pin initially blocked
7 
    PWM_TRIS = 1;
8 
 
9 
    /* Initialize PWM module */
10 
    PR2 = 0xF9; // 4ms @ 16MHz
11 
    CCP1CONbits.P1M = 0b00; // Single output, P1A modulated only
12 
    CCP1CONbits.CCP1M = 0b1100; // PWM mode, P1A active-high, P1B active-high
13 
 
14 
    // Idle the output till width is specified
15 
    CCPR1L = 0x00;
16 
    CCP1CONbits.DC1B = 0b00;
17 
 
18 
    /* Initialize Timer 2 */
19 
    PIR1bits.TMR2IF = 0; // Clear the interrupt flag for Timer 2
20 
    T2CONbits.T2CKPS = 0b11; // Set a prescaler of 64
21 
    T2CONbits.TMR2ON = 1; // Enable the timer
22 
 
23 
    // Wait for the timer to overflow before enabling output
24 
    while (!PIR1bits.TMR2IF);
25 
    PWM_TRIS = 0;
26 
}
27 
 
28 
void PWM_Set_Width(int width_us) {
29 
    // Set the pulse duration to the requested width
30 
    int value = width_us / 4;
31 
    CCPR1L = value >> 2;
32 
    CCP1CONbits.DC1B = value;
33 
}