Problema de recepción (Rx) UART de PIC32

Navega tus respuestas
0

Estoy tratando de construir una comunicación muy básica entre PIC32MX274F256D y una computadora portátil a través de un convertidor de 3.3 v usb a ttl.

La transmisión de datos desde PIC32 al terminal serial funciona bien. La recepción de datos desde el terminal serie, por otro lado, hace No funciona en absoluto. No se utilizan interrupciones.

  • He habilitado Tx y Rx en U1CON register.
  • La velocidad en baudios es correcta (ya que recibo los datos correctos en el terminal en 115200)
  • Las conexiones son correctas
  • Los datos se envían correctamente desde el convertidor al pin PIC Rx (probado con el osciloscopio)
  • He configurado la selección de pines periféricos en lugar ... correctamente

Sin embargo, cuando conecté el depurador ICD3, noté que dentro de la función de recepción de UART, el indicador U1STAbits.URXDA , que se activa cuando los datos están disponibles en el búfer de recepción, nunca se activa y el programa permanece en ese bucle de verificación "while" siempre. ¿Por qué sucede esto ya que los datos se pueden ver en el pin Rx del microcontrolador?

Adjunto la función de recepción de UART y el archivo main.c en caso de que note algo que no. 

uint8_t uart_RcvString( uint8_t * message, uint8_t maxLength){           // the function returns the number of characters that have been read message
                                                                      // is the character by character array that is received from docklight
    uint8_t numBytes = 0;

    while(numBytes < maxLength){                                 // while message not complete,
        while(!U1STAbits.URXDA);                              // and data is available,
            *message = U1RXREG;                                 // read the data from the 8-bit buffer
        if(*message == '\n' || *message == '\r'){
            *message = '
#pragma config AI2C1 = OFF             // Alternate I/O Select for I2C1 (I2C1 uses the ASDA1/ASCL1 pins)
#pragma config AI2C2 = OFF             // Alternate I/O Select for I2C2 (I2C2 uses the ASDA2/ASCL2 pins)
#pragma config PMDL1WAY = ON           // Peripheral Module Disable Configuration (Allow multiple reconfigurations)
#pragma config IOL1WAY = ON            // Peripheral Pin Select Configuration (Allow multiple reconfigurations)
#pragma config FUSBIDIO = OFF          // USB USID Selection (Controlled by the USB Module)

// DEVCFG2
#pragma config FPLLIDIV = DIV_4         // PLL Input Divider (2x Divider)
#pragma config FPLLMUL = MUL_24         // PLL Multiplier (24x Multiplier)
#pragma config FPLLICLK = PLL_POSC      // System PLL Input Clock Selection (POSC is input to the System PLL)
#pragma config UPLLIDIV = DIV_4         // USB PLL Input Divider (4x Divider)
#pragma config UPLLEN = ON              // USB PLL Enable (USB PLL Enabled)
#pragma config FPLLODIV = DIV_2         // System PLL Output Clock Divider (PLL Divide by 2)
#pragma config BOREN = OFF              // Brown-Out Reset (BOR) Enable (Enable BOR)
#pragma config DSBOREN = OFF            // Deep Sleep BOR Enable (Enable ZPBOR during Deep Sleep Mode)
#pragma config DSWDTPS = DSPS32         // Deep Sleep Watchdog Timer Postscaler (1:2^36)
#pragma config DSWDTOSC = SOSC          // Deep Sleep WDT Reference Clock Selection (Select SOSC as DSWDT Reference Clock)
#pragma config DSWDTEN = OFF            // Deep Sleep Watchdog Timer Enable (Disable DSWDT during Deep Sleep Mode)
#pragma config FDSEN = OFF              // Deep Sleep Enable (Disable DSEN bit in DSCON)

// DEVCFG1
#pragma config FNOSC = SPLL             // Oscillator Selection Bits (Primary Osc (HS,EC, XT))
#pragma config FSOSCEN = ON             // Secondary Oscillator Enable (Enabled)
#pragma config IESO = ON                // Internal/External Switch Over (Enabled)
#pragma config POSCMOD = HS             // Primary Oscillator Configuration (HS osc mode)
#pragma config OSCIOFNC = OFF           // CLKO Output Signal Active on the OSCO Pin (Disabled)
#pragma config FPBDIV = DIV_1           // Peripheral Clock Divisor (Pb_Clk is Sys_Clk/1)
#pragma config FCKSM = CSDCMD           // Clock Switching and Monitor Selection (Clock Switch Disable, FSCM Disabled)
#pragma config WDTPS = PS16384          // Watchdog Timer Postscaler (1:16384)
#pragma config WDTSPGM = ON             // Watchdog Timer Stop During Flash Programming (Watchdog Timer stops during Flash programming)
#pragma config WINDIS = OFF             // Watchdog Timer Window Enable (Watchdog Timer is in Non-Window Mode)
#pragma config FWDTEN = OFF             // Watchdog Timer Enable (WDT Disabled (SWDTEN Bit Controls))
#pragma config FWDTWINSZ = WINSZ_25     // Watchdog Timer Window Size (Window Size is 25%)

// DEVCFG0
#pragma config JTAGEN = OFF             // JTAG Enable (JTAG Disabled)
#pragma config ICESEL = ICS_PGx2        // ICE/ICD Comm Channel Select (Communicate on PGEC2/PGED2)
#pragma config PWP = OFF                // Program Flash Write Protect (Disable)
#pragma config SMCLR = MCLR_NORM        // Soft Master Clear Enable (MCLR pin generates a normal system Reset)
#pragma config BWP = OFF                // Boot Flash Write Protect bit (Protection Disabled)
#pragma config CP = OFF                 // Code Protect (Protection Disabled)

/*
 * 
 */
int main(void) {

    //===============================PERIPHERAL PIN SELECT==============================================
    uint32_t dmaVal, irqVal;
    unlock_OSCCON(&irqVal, &dmaVal);
    OSCCONbits.UFRCEN = 0;   /**< Disable Internal RC Oscillator*/
    CFGCONbits.IOLOCK = 0;   /**< Pin Select Unlock bit*/

    // Configure PIC32 pins as outputs/inputs

    SPI_MISO_PIN = INPUT;       /**< Set RC1  pin as input for the MISO2 pin*/  //    TRISCSET = _TRISC_TRISC1_MASK;  
    SPI_MOSI_PIN = OUTPUT;      /**< Set RA1  pin as output for the MOSI2 pin*/ //    TRISACLR = _TRISA_TRISA1_MASK; 
    SPI_SCK_PIN = OUTPUT;       /**< Set RB14 pin as output for the SCK2 pin*/  //    TRISBCLR = _TRISB_TRISB14_MASK; 

    TRISBCLR = _TRISB_TRISB3_MASK;        /**< Set RB3 pin as output for the UART1 Tx pin*/   
    TRISBSET = _TRISB_TRISB2_MASK;        /**< Set RB2 pin as input for the UART1 Rx pin*/   

    FLASH_CS_PIN = OUTPUT;      /**< Set RA7  pin as output for the flash enable pin*/  // TRISACLR = _TRISA_TRISA7_MASK;
    LORA_CS_PIN = OUTPUT;       /**< Set RA10  pin as output for the LoRa enable pin*/  // TRISACLR = _TRISA_TRISA10_MASK;
    CHGR_CEN_PIN = OUTPUT;      /**< Set RC3 pin as output for the charger enable pin*/ // TRISCCLR = _TRISC_TRISC3_MASK;  

    // Select the peripheral pins (PPS) for UART, SPI, I2C protocols
    U1RXRbits.U1RXR = 0x04;  /**< Place Rx of UART1 to pin RB2*/
    RPB3Rbits.RPB3R = 0x01;  /**< Place Tx of UART1 to pin RB3*/

    SDI2Rbits.SDI2R = 0x06;  /**< Place MISO pin of SPI2 to pin RC1*/
    RPA1Rbits.RPA1R = 0x04;  /**< Place MOSI pin of SPI2 to pin RA1*/
    // SCK1 is placed by default to RB15 pin when the SPI module is enabled

    // SDA1 is placed by default to RB9 pin when the I2C1 module is enabled
    // SCL1 is placed by default to RB8 pin when the I2C1 module is enabled

    CNPUAbits.CNPUA1 = 1; //Enable Weak Pull up ON MOSI Line
    CNPUCbits.CNPUC1 = 1; //Enable Weak Pull up ON MISO Line
    CNPUBbits.CNPUB15 = 1; //Enable Weak Pull up ON SCK Line
    CNPDBbits.CNPDB14 = 1; //Enable Weak Pull Down ON ID PIN so it is not floating

    CFGCONbits.IOLOCK = 1;    /**<Pin Select lock bit*/
    lock_OSCCON(irqVal, dmaVal);

    //====================Peripheral setup=======================

    unsigned char k = 0;
    char b = 0;
    char *array = &b;

    LED_PIN = OUTPUT;
    LED_OFF();   

    uart_Setup();
    I2C_Master_Setup();

    uart_SndString("Give password\n");
    k = uart_RcvString(array, 4);

    if(*(array+0) == 'P' && *(array+1) == 'A' && *(array+2) == 'S' && *(array+3) == 'S')
       uart_SndString("Correct password\n");
    else 
       uart_SndString("Wrong password\n");

    while(1){

        LED_ON();
        _CP0_SET_COUNT(0);
        while(_CP0_GET_COUNT()< 23994230);   // 23994230 = 1 sec
        LED_OFF();
        _CP0_SET_COUNT(0);
        while(_CP0_GET_COUNT()< 5000000);   


    }
    return (EXIT_SUCCESS);
}

';
            break;
        }
        message++;
        numBytes++;   
    }
    return numBytes;
}

El siguiente código es el principal. archivo c El programa se apila en el comando k = uart_RcvString(array, 4); antes del bucle while. 

uint8_t uart_RcvString( uint8_t * message, uint8_t maxLength){           // the function returns the number of characters that have been read message
                                                                      // is the character by character array that is received from docklight
    uint8_t numBytes = 0;

    while(numBytes < maxLength){                                 // while message not complete,
        while(!U1STAbits.URXDA);                              // and data is available,
            *message = U1RXREG;                                 // read the data from the 8-bit buffer
        if(*message == '\n' || *message == '\r'){
            *message = '
#pragma config AI2C1 = OFF             // Alternate I/O Select for I2C1 (I2C1 uses the ASDA1/ASCL1 pins)
#pragma config AI2C2 = OFF             // Alternate I/O Select for I2C2 (I2C2 uses the ASDA2/ASCL2 pins)
#pragma config PMDL1WAY = ON           // Peripheral Module Disable Configuration (Allow multiple reconfigurations)
#pragma config IOL1WAY = ON            // Peripheral Pin Select Configuration (Allow multiple reconfigurations)
#pragma config FUSBIDIO = OFF          // USB USID Selection (Controlled by the USB Module)

// DEVCFG2
#pragma config FPLLIDIV = DIV_4         // PLL Input Divider (2x Divider)
#pragma config FPLLMUL = MUL_24         // PLL Multiplier (24x Multiplier)
#pragma config FPLLICLK = PLL_POSC      // System PLL Input Clock Selection (POSC is input to the System PLL)
#pragma config UPLLIDIV = DIV_4         // USB PLL Input Divider (4x Divider)
#pragma config UPLLEN = ON              // USB PLL Enable (USB PLL Enabled)
#pragma config FPLLODIV = DIV_2         // System PLL Output Clock Divider (PLL Divide by 2)
#pragma config BOREN = OFF              // Brown-Out Reset (BOR) Enable (Enable BOR)
#pragma config DSBOREN = OFF            // Deep Sleep BOR Enable (Enable ZPBOR during Deep Sleep Mode)
#pragma config DSWDTPS = DSPS32         // Deep Sleep Watchdog Timer Postscaler (1:2^36)
#pragma config DSWDTOSC = SOSC          // Deep Sleep WDT Reference Clock Selection (Select SOSC as DSWDT Reference Clock)
#pragma config DSWDTEN = OFF            // Deep Sleep Watchdog Timer Enable (Disable DSWDT during Deep Sleep Mode)
#pragma config FDSEN = OFF              // Deep Sleep Enable (Disable DSEN bit in DSCON)

// DEVCFG1
#pragma config FNOSC = SPLL             // Oscillator Selection Bits (Primary Osc (HS,EC, XT))
#pragma config FSOSCEN = ON             // Secondary Oscillator Enable (Enabled)
#pragma config IESO = ON                // Internal/External Switch Over (Enabled)
#pragma config POSCMOD = HS             // Primary Oscillator Configuration (HS osc mode)
#pragma config OSCIOFNC = OFF           // CLKO Output Signal Active on the OSCO Pin (Disabled)
#pragma config FPBDIV = DIV_1           // Peripheral Clock Divisor (Pb_Clk is Sys_Clk/1)
#pragma config FCKSM = CSDCMD           // Clock Switching and Monitor Selection (Clock Switch Disable, FSCM Disabled)
#pragma config WDTPS = PS16384          // Watchdog Timer Postscaler (1:16384)
#pragma config WDTSPGM = ON             // Watchdog Timer Stop During Flash Programming (Watchdog Timer stops during Flash programming)
#pragma config WINDIS = OFF             // Watchdog Timer Window Enable (Watchdog Timer is in Non-Window Mode)
#pragma config FWDTEN = OFF             // Watchdog Timer Enable (WDT Disabled (SWDTEN Bit Controls))
#pragma config FWDTWINSZ = WINSZ_25     // Watchdog Timer Window Size (Window Size is 25%)

// DEVCFG0
#pragma config JTAGEN = OFF             // JTAG Enable (JTAG Disabled)
#pragma config ICESEL = ICS_PGx2        // ICE/ICD Comm Channel Select (Communicate on PGEC2/PGED2)
#pragma config PWP = OFF                // Program Flash Write Protect (Disable)
#pragma config SMCLR = MCLR_NORM        // Soft Master Clear Enable (MCLR pin generates a normal system Reset)
#pragma config BWP = OFF                // Boot Flash Write Protect bit (Protection Disabled)
#pragma config CP = OFF                 // Code Protect (Protection Disabled)

/*
 * 
 */
int main(void) {

    //===============================PERIPHERAL PIN SELECT==============================================
    uint32_t dmaVal, irqVal;
    unlock_OSCCON(&irqVal, &dmaVal);
    OSCCONbits.UFRCEN = 0;   /**< Disable Internal RC Oscillator*/
    CFGCONbits.IOLOCK = 0;   /**< Pin Select Unlock bit*/

    // Configure PIC32 pins as outputs/inputs

    SPI_MISO_PIN = INPUT;       /**< Set RC1  pin as input for the MISO2 pin*/  //    TRISCSET = _TRISC_TRISC1_MASK;  
    SPI_MOSI_PIN = OUTPUT;      /**< Set RA1  pin as output for the MOSI2 pin*/ //    TRISACLR = _TRISA_TRISA1_MASK; 
    SPI_SCK_PIN = OUTPUT;       /**< Set RB14 pin as output for the SCK2 pin*/  //    TRISBCLR = _TRISB_TRISB14_MASK; 

    TRISBCLR = _TRISB_TRISB3_MASK;        /**< Set RB3 pin as output for the UART1 Tx pin*/   
    TRISBSET = _TRISB_TRISB2_MASK;        /**< Set RB2 pin as input for the UART1 Rx pin*/   

    FLASH_CS_PIN = OUTPUT;      /**< Set RA7  pin as output for the flash enable pin*/  // TRISACLR = _TRISA_TRISA7_MASK;
    LORA_CS_PIN = OUTPUT;       /**< Set RA10  pin as output for the LoRa enable pin*/  // TRISACLR = _TRISA_TRISA10_MASK;
    CHGR_CEN_PIN = OUTPUT;      /**< Set RC3 pin as output for the charger enable pin*/ // TRISCCLR = _TRISC_TRISC3_MASK;  

    // Select the peripheral pins (PPS) for UART, SPI, I2C protocols
    U1RXRbits.U1RXR = 0x04;  /**< Place Rx of UART1 to pin RB2*/
    RPB3Rbits.RPB3R = 0x01;  /**< Place Tx of UART1 to pin RB3*/

    SDI2Rbits.SDI2R = 0x06;  /**< Place MISO pin of SPI2 to pin RC1*/
    RPA1Rbits.RPA1R = 0x04;  /**< Place MOSI pin of SPI2 to pin RA1*/
    // SCK1 is placed by default to RB15 pin when the SPI module is enabled

    // SDA1 is placed by default to RB9 pin when the I2C1 module is enabled
    // SCL1 is placed by default to RB8 pin when the I2C1 module is enabled

    CNPUAbits.CNPUA1 = 1; //Enable Weak Pull up ON MOSI Line
    CNPUCbits.CNPUC1 = 1; //Enable Weak Pull up ON MISO Line
    CNPUBbits.CNPUB15 = 1; //Enable Weak Pull up ON SCK Line
    CNPDBbits.CNPDB14 = 1; //Enable Weak Pull Down ON ID PIN so it is not floating

    CFGCONbits.IOLOCK = 1;    /**<Pin Select lock bit*/
    lock_OSCCON(irqVal, dmaVal);

    //====================Peripheral setup=======================

    unsigned char k = 0;
    char b = 0;
    char *array = &b;

    LED_PIN = OUTPUT;
    LED_OFF();   

    uart_Setup();
    I2C_Master_Setup();

    uart_SndString("Give password\n");
    k = uart_RcvString(array, 4);

    if(*(array+0) == 'P' && *(array+1) == 'A' && *(array+2) == 'S' && *(array+3) == 'S')
       uart_SndString("Correct password\n");
    else 
       uart_SndString("Wrong password\n");

    while(1){

        LED_ON();
        _CP0_SET_COUNT(0);
        while(_CP0_GET_COUNT()< 23994230);   // 23994230 = 1 sec
        LED_OFF();
        _CP0_SET_COUNT(0);
        while(_CP0_GET_COUNT()< 5000000);   


    }
    return (EXIT_SUCCESS);
}

';
            break;
        }
        message++;
        numBytes++;   
    }
    return numBytes;
}

Gracias por tu tiempo.

    
pregunta Lefteris

1 respuesta

1

¡Problema resuelto!

Los pines que uso para la comunicación UART son por defecto entradas analógicas. Deshabilité esta función y convertí los pines a digital haciendo esto: 

ANSELBbits.ANSB2 = 0;
ANSELBbits.ANSB3 = 0;

y funcionó bien.

Los registros para esto están en la p.154 de la hoja de datos de PIC32MX2xx Tabla 12-4

    
respondido por el Lefteris

Lea otras preguntas en las etiquetas

El voltaje directo Vf de un diodo LCD 20x4 Mostrar solo los píxeles de puño y tercera fila en