[PIC] Independent PWM Control (dsPIC33f)

Code C - [expand]
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void init_PWM()
{
    //P1TCON = 0x0000;
    _PTMOD = 0x0; // PWM Time Base Mode Select bits  PWM time base operates in a Free-Running mode
    _PTCKPS = 0x0; // PWM Time Base Input Clock Prescale Select bits PWM time base input clock period is TCY (1:1 prescale)
    _PTOPS = 0x00; // PWM Time Base Output Postscale Select bits. 1:1 postscale
    _PTEN = 1; // PWM Time Base Timer Enable bit. PWM time base is on
 
    PTPER = 499; // PWM Time Base Period Value bits / PTPER+1  fPWM=20kHz fCY=20 MHz
 
    /*~~~~~~~~~~~~~~~~~~~~~~~ PWM1 Configuration ~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
    _PEN1H      = 0x1;                  /* PWM1H is controlled by PWM module */
    _PEN1L      = 0x1;                  /* PWM1L is controlled by PWM module */
    _PEN2H      = 0x1;
    _PEN2L      = 0x1;
    _PEN3H      = 0x1;
    _PEN3L      = 0x1;
    _PMOD1      = 0x0;                  /* Select Independent Output PWM mode */
    _PMOD2      = 0x0;
    _PMOD3      = 0x0;
    PDC1 = 500;             /* Initial Duty cycle PDCx/2 */
    PDC2 = 500;
    PDC3 = 500;
 
    PTCONbits.PTEN       = 1;           /* Enable the PWM Module */
 
}