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MSP430FR2422: UART receive data try with external UART

Part Number: MSP430FR2422

Hi,

I am working on MSP430FR2422 and i am new to this board. I am currently working on the UART and I am trying to receive the data coming from UART external peripheral and I want to receive the data but here I am not able to do that . I am giving input to UART com port that should go to the P1.5 which is the UCA0RXD which we are using. Here the main problem we are facing is that when the ISR is called the routine is executed and the dat is not being saved in UCARXBUF . I am attaching the code and also I have seen the driver as well as register library example from the resource explorer but I didn't find any significant clue from that.

/******************************************************************************
#include "driverlib.h"
//#include "Board.h"
#define GPIO_PORT_UCA0TXD GPIO_PORT_P1
#define GPIO_PIN_UCA0TXD GPIO_PIN4
#define GPIO_FUNCTION_UCA0TXD GPIO_PRIMARY_MODULE_FUNCTION
#define GPIO_PORT_UCA0RXD GPIO_PORT_P1
#define GPIO_PIN_UCA0RXD GPIO_PIN5
#define GPIO_FUNCTION_UCA0RXD GPIO_PRIMARY_MODULE_FUNCTION
uint16_t i;
uint8_t RXData = 0, TXData = 0;
char mystr[20]="Hello_World\r\n";
unsigned long int m=0;
uint8_t check = 0;
#include<stdio.h>

void main(void)
{
//Stop Watchdog Timer
WDT_A_hold(WDT_A_BASE);

//Set ACLK = REFOCLK with clock divider of 1
CS_initClockSignal(CS_ACLK,CS_REFOCLK_SELECT,CS_CLOCK_DIVIDER_1);
//Set SMCLK = DCO with frequency divider of 1
CS_initClockSignal(CS_SMCLK,CS_DCOCLKDIV_SELECT,CS_CLOCK_DIVIDER_1);
//Set MCLK = DCO with frequency divider of 1
CS_initClockSignal(CS_MCLK,CS_DCOCLKDIV_SELECT,CS_CLOCK_DIVIDER_1);

//Configure UART pins
GPIO_setAsPeripheralModuleFunctionInputPin(
GPIO_PORT_UCA0TXD,
GPIO_PIN_UCA0TXD,
GPIO_FUNCTION_UCA0TXD
);
GPIO_setAsPeripheralModuleFunctionInputPin(
GPIO_PORT_UCA0RXD,
GPIO_PIN_UCA0RXD,
GPIO_FUNCTION_UCA0RXD
);

/*
* Disable the GPIO power-on default high-impedance mode to activate
* previously configured port settings
*/
PMM_unlockLPM5();

//Configure UART
//SMCLK = 1MHz, Baudrate = 115200
//UCBRx = 8, UCBRFx = 0, UCBRSx = 0xD6, UCOS16 = 0
EUSCI_A_UART_initParam param = {0};
param.selectClockSource = EUSCI_A_UART_CLOCKSOURCE_SMCLK;
param.clockPrescalar = 8;
param.firstModReg = 0;
param.secondModReg = 0xD6;
param.parity = EUSCI_A_UART_NO_PARITY;
param.msborLsbFirst = EUSCI_A_UART_LSB_FIRST;
param.numberofStopBits = EUSCI_A_UART_ONE_STOP_BIT;
param.uartMode = EUSCI_A_UART_MODE;
param.overSampling = EUSCI_A_UART_LOW_FREQUENCY_BAUDRATE_GENERATION;

if (STATUS_FAIL == EUSCI_A_UART_init(EUSCI_A0_BASE, &param)) {
return;
}

EUSCI_A_UART_enable(EUSCI_A0_BASE);

EUSCI_A_UART_clearInterrupt(EUSCI_A0_BASE,
EUSCI_A_UART_TRANSMIT_INTERRUPT);

// Enable USCI_A0 RX interrupt
EUSCI_A_UART_enableInterrupt(EUSCI_A0_BASE,
EUSCI_A_UART_TRANSMIT_INTERRUPT);

// Enable global interrupts
__enable_interrupt();
while (1)
{
// Increment TX data

// Load data onto buffer
int f;
for(f=0;mystr[f]!='\0';f++)
{
//UCA0TXBUF=mystr[f];
EUSCI_A_UART_transmitData(EUSCI_A0_BASE,mystr[f]);

}

for(m=0;m<10000;m++);
// while(check != 1);
//check = 0;
}
}
//******************************************************************************
//
//This is the USCI_A0 interrupt vector service routine.
//
//******************************************************************************
#if defined(__TI_COMPILER_VERSION__) || defined(__IAR_SYSTEMS_ICC__)
#pragma vector=USCI_A0_VECTOR
__interrupt
#elif defined(__GNUC__)
__attribute__((interrupt(USCI_A0_VECTOR)))
#endif
void EUSCI_A0_ISR(void)
{
switch(__even_in_range(UCA0IV,USCI_UART_UCTXCPTIFG))
{
case USCI_NONE: break;
case USCI_UART_UCTXIFG:
// RXData=UCA0RXBUF;
RXData = EUSCI_A_UART_receiveData(EUSCI_A0_BASE);
// Check value
//if(!(RXData == TXData))
//{
// while(1);
//}
//check =1;
break;
case USCI_UART_UCRXIFG: break;
case USCI_UART_UCSTTIFG: break;
case USCI_UART_UCTXCPTIFG: break;
}
}

  • > EUSCI_A_UART_clearInterrupt(EUSCI_A0_BASE,EUSCI_A_UART_TRANSMIT_INTERRUPT);

    > EUSCI_A_UART_enableInterrupt(EUSCI_A0_BASE,EUSCI_A_UART_TRANSMIT_INTERRUPT);

    Based on the rest of the code, you should be enabling the receive interrupt (UCRXIE), something like:

    > EUSCI_A_UART_clearInterrupt(EUSCI_A0_BASE,EUSCI_A_UART_RECEIVE_INTERRUPT);

    > EUSCI_A_UART_enableInterrupt(EUSCI_A0_BASE,EUSCI_A_UART_RECEIVE_INTERRUPT);

    -------------------

    > case USCI_UART_UCTXIFG:
    > // RXData=UCA0RXBUF;
    > RXData = EUSCI_A_UART_receiveData(EUSCI_A0_BASE);

    This is detecting the transmit interrupt, not the receive interrupt. Replace the first line with:

    > case USCI_UART_UCRXIFG:
    :

  • Hi there thanks for replying , my issue is resolved with your help

    I am attaching my final code as well

    /* --COPYRIGHT--,BSD
    * Copyright (c) 2017, Texas Instruments Incorporated
    * All rights reserved.
    *
    * Redistribution and use in source and binary forms, with or without
    * modification, are permitted provided that the following conditions
    * are met:
    *
    * * Redistributions of source code must retain the above copyright
    * notice, this list of conditions and the following disclaimer.
    *
    * * Redistributions in binary form must reproduce the above copyright
    * notice, this list of conditions and the following disclaimer in the
    * documentation and/or other materials provided with the distribution.
    *
    * * Neither the name of Texas Instruments Incorporated nor the names of
    * its contributors may be used to endorse or promote products derived
    * from this software without specific prior written permission.
    *
    * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
    * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
    * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
    * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
    * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
    * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
    * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
    * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
    * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
    * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
    * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
    * --/COPYRIGHT--*/
    //******************************************************************************
    //! EUSCI_A0 External Loopback test using EUSCI_A_UART_init API
    //!
    //! Description: This demo connects TX to RX of the MSP430 UART
    //! The example code shows proper initialization of registers
    //! and interrupts to receive and transmit data.
    //!
    //! SMCLK = MCLK = BRCLK = DCOCLKDIV = ~1MHz, ACLK = 32.768kHz
    //!
    //!
    //! MSP430FR2xx_4xx Board
    //! -----------------
    //! RST -| UCA0TXD|----|
    //! | | |
    //! | | |
    //! | UCA0RXD|----|
    //! | |
    //!
    //! This example uses the following peripherals and I/O signals. You must
    //! review these and change as needed for your own board:
    //! - UART peripheral
    //! - GPIO Port peripheral (for UART pins)
    //! - UCA0TXD
    //! - UCA0RXD
    //!
    //! This example uses the following interrupt handlers. To use this example
    //! in your own application you must add these interrupt handlers to your
    //! vector table.
    //! - USCI_A0_VECTOR.
    //******************************************************************************
    #include "driverlib.h"
    //#include "Board.h"
    #define GPIO_PORT_UCA0TXD GPIO_PORT_P1
    #define GPIO_PIN_UCA0TXD GPIO_PIN4
    #define GPIO_FUNCTION_UCA0TXD GPIO_PRIMARY_MODULE_FUNCTION
    #define GPIO_PORT_UCA0RXD GPIO_PORT_P1
    #define GPIO_PIN_UCA0RXD GPIO_PIN5
    #define GPIO_FUNCTION_UCA0RXD GPIO_PRIMARY_MODULE_FUNCTION
    uint16_t i;
    uint8_t RXData = 0, TXData = 0;
    char mystr[20]="Hello_World\r\n";
    char receive[20];
    uint16_t x;
    unsigned long int m=0;
    uint8_t check = 0;
    #include<stdio.h>

    void main(void)
    {
    //Stop Watchdog Timer
    WDT_A_hold(WDT_A_BASE);

    //Set ACLK = REFOCLK with clock divider of 1
    CS_initClockSignal(CS_ACLK,CS_REFOCLK_SELECT,CS_CLOCK_DIVIDER_1);
    //Set SMCLK = DCO with frequency divider of 1
    CS_initClockSignal(CS_SMCLK,CS_DCOCLKDIV_SELECT,CS_CLOCK_DIVIDER_1);
    //Set MCLK = DCO with frequency divider of 1
    CS_initClockSignal(CS_MCLK,CS_DCOCLKDIV_SELECT,CS_CLOCK_DIVIDER_1);

    //Configure UART pins
    GPIO_setAsPeripheralModuleFunctionInputPin(
    GPIO_PORT_UCA0TXD,
    GPIO_PIN_UCA0TXD,
    GPIO_FUNCTION_UCA0TXD
    );
    GPIO_setAsPeripheralModuleFunctionInputPin(
    GPIO_PORT_UCA0RXD,
    GPIO_PIN_UCA0RXD,
    GPIO_FUNCTION_UCA0RXD
    );

    /*
    * Disable the GPIO power-on default high-impedance mode to activate
    * previously configured port settings
    */
    PMM_unlockLPM5();

    //Configure UART
    //SMCLK = 1MHz, Baudrate = 115200
    //UCBRx = 8, UCBRFx = 0, UCBRSx = 0xD6, UCOS16 = 0
    EUSCI_A_UART_initParam param = {0};
    param.selectClockSource = EUSCI_A_UART_CLOCKSOURCE_SMCLK;
    param.clockPrescalar = 8;
    param.firstModReg = 0;
    param.secondModReg = 0xD6;
    param.parity = EUSCI_A_UART_NO_PARITY;
    param.msborLsbFirst = EUSCI_A_UART_LSB_FIRST;
    param.numberofStopBits = EUSCI_A_UART_ONE_STOP_BIT;
    param.uartMode = EUSCI_A_UART_MODE;
    param.overSampling = EUSCI_A_UART_LOW_FREQUENCY_BAUDRATE_GENERATION;

    if (STATUS_FAIL == EUSCI_A_UART_init(EUSCI_A0_BASE, &param)) {
    return;
    }

    EUSCI_A_UART_enable(EUSCI_A0_BASE);

    EUSCI_A_UART_clearInterrupt(EUSCI_A0_BASE,
    EUSCI_A_UART_RECEIVE_INTERRUPT);

    // Enable USCI_A0 RX interrupt
    EUSCI_A_UART_enableInterrupt(EUSCI_A0_BASE,
    EUSCI_A_UART_RECEIVE_INTERRUPT);

    // Enable global interrupts
    __enable_interrupt();
    while (1)
    {
    // Increment TX data

    // Load data onto buffer
    int f;
    for(f=0;mystr[f]!='\0';f++)
    {
    //UCA0TXBUF=mystr[f];
    EUSCI_A_UART_transmitData(EUSCI_A0_BASE,mystr[f]);
    while(EUSCI_A_UART_getInterruptStatus(EUSCI_A0_BASE, EUSCI_A_UART_RECEIVE_INTERRUPT_FLAG)){
    // Wait until complete
    }

    }
    // while(EUSCI_A_UART_getInterruptStatus(EUSCI_A0_BASE, EUSCI_A_UART_RECEIVE_INTERRUPT_FLAG)){
    // Wait until complete
    // }

    while(check != 1);
    check = 0;
    }
    }
    //******************************************************************************
    //
    //This is the USCI_A0 interrupt vector service routine.
    //
    //******************************************************************************
    #if defined(__TI_COMPILER_VERSION__) || defined(__IAR_SYSTEMS_ICC__)
    #pragma vector=USCI_A0_VECTOR
    __interrupt
    #elif defined(__GNUC__)
    __attribute__((interrupt(USCI_A0_VECTOR)))
    #endif
    void EUSCI_A0_ISR(void)
    {
    switch(__even_in_range(UCA0IV,USCI_UART_UCTXCPTIFG))
    {
    case USCI_NONE: break;
    case USCI_UART_UCRXIFG:
    // RXData=UCA0RXBUF;
    RXData = EUSCI_A_UART_receiveData(EUSCI_A0_BASE);
    // EUSCI_A_UART_transmitData(EUSCI_A0_BASE,RXData);

    // Check value
    /*if(!(RXData == TXData))
    {
    while(1);
    }
    check =1;*/
    break;
    case USCI_UART_UCTXIFG: break;
    case USCI_UART_UCSTTIFG: break;
    case USCI_UART_UCTXCPTIFG: break;
    }
    }

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