Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

PWM module of PIC18f46k22

Hayee

Member level 3
Joined
Mar 4, 2022
Messages
54
Helped
1
Reputation
2
Reaction score
3
Trophy points
8
Activity points
515
Hi
I am using CCP Module of PIC18f46k22 to generate PWM signal on CCP2 (Pin no 16) . All is working well if i load values only in CCPR2L register in run time and load the value in CCP2CON at starting of program.
but when I try to change the value of CCP2CON while running then there is no PWM on Pin.
I want to know that can I change the CCP2CON register value while running.
I want to check it weather it works or not because datasheet says that PWM is of 10 bit. Upper 8-Bits are in CCPR2L and Lower 2-Bits are in CCP2CON <5:4>
Kindly clear me if I am wrong.

Code:
void main(void) {
    
    uint8_t count = 0;
    uint8_t temp = 0;
    uint8_t temp2 = 0;
    uint8_t value = 0;
    
    uint8_t pwmArray[] = {71,73,76,79,81,83,86,89,92,96,97,101,104,107,109,112,114};
    
    OSCILLATOR_Init();
    PORT_Init();
    SPI1_Init();
    
    LCD(&PORTD, 0,1,2,3,4,5);   // set the connection between the MCU and the LCD
    LCD_Begin(16,2);            // initialize the LCD module with 16 rows and 2 columns (1602 LCD)
    
    // EUSART Settings   
    // Port, TXSTA1, RCSTA1, BAUDCON1, BaudRate Value
    setup_uart(UART_1, ASYNC_MODE | TXMIT_EN | HIGH_SPEED, SPEN_EN | RCVR_EN, BAUD_16BIT, 9600);
    setup_uart(UART_2, ASYNC_MODE | TXMIT_EN | HIGH_SPEED, SPEN_EN | RCVR_EN, BAUD_16BIT, 9600);
    
    setup_timer_3(T3_DIV_8 | T3_NO_SYNC_EXT_CLK | T3_ENABLE);
    set_timer_3(T3_Loadvalue);
    
    setup_timer_1(T1_DIV_1 | T1_NO_SYNC_EXT_CLK | T1_ENABLE);
    set_timer_1(T1_Loadvalue);
    
    setup_pwm();
    setup_timer_2(T2_ENABLE);
    set_timer_2(T2_Loadvalue);
    
    
    enable_interrupt(INT_TIMER1);
    enable_interrupt(INT_TIMER3);
    
    PERIPHERAL_Interrupts(ENABLE);
    GLOBAL_Interrupts(ENABLE);
    
    while(1)
    {
        if(!PORTBbits.RB7){
            while(!PORTBbits.RB7);
            
            if(count > 17) count = 0;
            else count++;
            
            value = pwmArray[count];
            
            temp = (uint8_t)(value << 4);
            temp = CCP2CON | temp;
            CCP2CON = temp;

            temp2 = (value >> 2);
            CCPR2L = temp2;
            
            LCD_Goto(1,2); printf("%x", temp);
            LCD_Goto(7,2); printf("%u", CCPR2L);
        }
    }
    return;
}

Code:
void setup_pwm(){
    CCP2CON = 0x0C; // CCP2M P2A,P2C: active high; P2B,P2D: active high;
                    // DC2B 3; P2M single;   
    CCPR2H = 0x00;  // CCPR2H 0;     
    CCPR2L = 0x3C;  // CCPR2L 60;   
    
    CCPTMRS0bits.C2TSEL = 0x0;// Selecting Timer2
}

Frequency of Timer 2 is set to 20KHz and can be seen on Proteus, while to change the duty cycle i have to load the values in CCPR2L and CCP2CON registers.
 

LaTeX Commands Quick-Menu:

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top