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PIC24FJ1024GB610 PWM

RF Can

New Member
Hi guys!

I recently bought a "Clicker 2 mikro bus" from Mikroelektronika. This comes with a 16-bit PIC24FJ1024GB610 microcontroller:
I'm able to communicate and load .HEX files in it. I loaded it up with a "Led Blinking" program on PORT B and worked too.

My problem is when I try to get a PWM signal out of it. For the moment: their PWM_Start() function seems to do nothing.
Then, I tried to program it "old school" fashion. Yet, nothing comes out of PIN # RF2. See below:

void PWMStep (void){
int PWMperiod=799;

TRISFbits.TRISF2 = 0; //Set RF2 as output
RPOR15bits.RP30R = 18; //OC1 Output to Pin PWM
LATFbits.LATF2 = 0; //Initialize RF2 as low
OC1CON1 = 0; // Clear registers
OC1CON2 = 0;
OC1CON2bits.SYNCSEL = 0b11111; // synchronized by itself
OC1CON1bits.OCTSEL = 0b111; // system clock is the source for output Compare
OC1CON1bits.OCM = 0b111;
OC1CON1bits.OCSIDL=1;
OC1RS = (int)(PWMperiod); // PWM period
OC1R = (int)((PWMperiod/2)); //50% initial duty cycle
}

void main(){

while(1){

PWMStep();

}

}

I tried this simple program just to get a 50% duty cycle PWM signal. For the moment, RF2 keeps a LOW state. No PWM at all.

Any help is appreciated. Many thanks,

RF Can
 

granddad

Well-Known Member
TRISFbits.TRISF2 = 0; //Set RF2 as output
RPOR15bits.RP30R = 18; //OC1 Output to Pin PWM
RPOR15bits.RP30R = 18; //OC1 Output to Pin PWM

Your PPS code the"18" is for CCP6 as the output ?
 
Last edited:

RF Can

New Member
RPOR15bits.RP30R = 18; //OC1 Output to Pin PWM

Your PPS code the"18" is for CCP6 as the output ?
Nice catch. I just saw on table 11-4 (p. 161 datasheet), OSC1 code is 13 (and not 18). I re-programmed it with the right value, but still nothing on PIN # RF2.
Do you have an ideal?
 

granddad

Well-Known Member
I seem to remember i did this bug chasing some time ago on that PIC ( just as a PWM exercise ) I will see if i can find the code , The CCP1CON1L[3-0] register comes to mind Just a guess !
 
Last edited:

RF Can

New Member
I seem to remember i did this bug chasing some time ago on that PIC ( just as a PWM exercise ) I will see if i can find the code , The CCP1CON1L[3-0] register comes to mind Just a guess !
OK thanks in advance if you find anything.
 

granddad

Well-Known Member
Not sure if this is any help. I was using timer 2 as clock . and OC3 , It was for a solar charge controller .
C:
    void OC_init() {
    TRISAbits.TRISA10 = 0; // OC3 OUTPUT
    Nop();
    OC3R = 0x8FFF;
    OC3RS = 0x08FC;
    OC3CON2bits.SYNCSEL = 0;
    OC3CON2bits.OCMPINV = 0;
    OC3CON1bits.OCTSEL = 0; //T2 clock
    OC3CON1bits.OCM = 0; // CONTINIOUS pwm mode = 5, 0=off
    PWM_rate=0;
   
}
void PWM_charge(int rate){
   OC3CON1bits.OCM = 0; // STOP pwm
   LATAbits.LATA10=0; // mosfet driver
   LCD_print(3,0," REG @ ");
   switch(rate){
    case 5:
       OC3R = 0xFF00;
       OC3CON1bits.OCM = 5;
       LCD_print(3,7,"  5% PWM ");
       break;
    case 25:
       OC3R = 0xCFFF;
       OC3CON1bits.OCM = 5;
        LCD_print(3,7," 25% PWM ");
       break;
    case 50:
       OC3R = 0x8FFF;
       OC3CON1bits.OCM = 5;
        LCD_print(3,7," 50% PWM ");
       break;
    case 75:
       OC3R = 0x4FFF;
       OC3CON1bits.OCM = 5;
       LCD_print(3,7," 75% PWM ");
       break;
  }
 

RF Can

New Member
I finally took another approach (see below), and works fine for RF2, RF5, RF8, D0 and D11 PWM lines of this MCU model. There's only RF4 I wasn't able to get any modulated output. I'll need to investigate deeper about this pin... Anyways: rare are the projects you need 6 PWM outputs...

void main(){
int j;

while(1){
TRISDbits.TRISD11 = 0;
RPOR6bits.RP12R = 13;
LATDbits.LATD11=0;
/* Reset PWM */
OC1CON1 = 0x0000;
OC1CON2 = 0x0000;

// config timer3
T3CON = 0x00;
TMR3 = 0x00; //Clear contents of the timer register
PR3 = 0xFFFF;


T3CONbits.TCKPS = 0x03; //1:256 prescaler
// configure PWM
OC1CON2 = 0x001F; /* Sync with This OC module*/
//OC1CON1 = 0x1C08; /* Clock source Fcyc, trigger mode 1*/
OC1CON1 = 0x0408; /* Clock source timer3, trigger mode 1*/
/* enable the PWM */
OC1CON1 = OC1CON1 | 0x0006; /* Mode 6, Edge-aligned PWM Mode */

T3CONbits.TON = 1; //Start Timer3
OC1RS = 1250;

for(;;){
for(j=0; j<1250; j++){
OC1R = j;

if(j==1249){
j=0;
}
}
}
}
}

Thanks for your time and wish you the best for 2021!
RF Can
 

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