CCS/MSP430F5529: UART receives multi-byte array is overwritten

Tool/software: Code Composer Studio

Dear team,

The data returned by the sensor is a group of 8-byte data, but I only got the last byte of data through interruption. How can I solve this situation?

The problem now is that when the serial port receives 8 bytes of data, it will be lost. Normally, the lengt value should be 8 every time, but it is not every time during the test, sometimes 4 times and sometimes 6 times, and it is always impossible to receive all stable data.

#include <msp430.h>

#include "driverlib/MSP430F5xx_6xx/driverlib.h"

#include <stdint.h>

#include <stdbool.h>

#include <string.h>

#include <stdio.h>

 

extern int TVOC[9];

 

int flag = 0;

char fff[1];

 

int RxBuf[20];

static int lengt = 0;

float TVOC0;

char TVOC[9];

uint8_t TVOCSend[9]={0xFF,0x00,0x86,0x00,0x00,0x00,0x00,0x00,0x7A};   //用于查询空气质量传感器的命令

int TVOCtest[9];   //用于接收空气质量传递过来的数据

 

int main(void)

{

   WDTCTL = WDTPW + WDTHOLD;                 // Stop WDT

   UART0_Init();

   UART2_Init();

   while (getTVOC() == false)//让空气质量传感器能够正常地采集数据

   {

       mDelay(1000);

   }

   while(1)

   {

       getTVOC();

       mDelay(1000);

   }

}

 

void UART0_Init()

{

       //P3.4,5 = USCI_A2 TXD/RXD

       GPIO_setAsPeripheralModuleFunctionInputPin(GPIO_PORT_P3,GPIO_PIN4 + GPIO_PIN5);

 

       //Baudrate = 9600, clock freq = 1.048MHz

       //UCBRx = 109, UCBRFx = 0, UCBRSx = 2, UCOS16 = 0

       USCI_A_UART_initParam param = {0};

       param.selectClockSource = USCI_A_UART_CLOCKSOURCE_SMCLK;

       param.clockPrescalar = 109;

       param.firstModReg = 0;

       param.secondModReg = 2;

       param.parity = USCI_A_UART_NO_PARITY;

       param.msborLsbFirst = USCI_A_UART_LSB_FIRST;

       param.numberofStopBits = USCI_A_UART_ONE_STOP_BIT;

       param.uartMode = USCI_A_UART_MODE;

       param.overSampling = USCI_A_UART_LOW_FREQUENCY_BAUDRATE_GENERATION;

       //param.overSampling = USCI_A_UART_OVERSAMPLING_BAUDRATE_GENERATION;

 

       if (STATUS_FAIL == USCI_A_UART_init(USCI_A0_BASE, &param))

       {

           return;

       }

       //Enable UART module for operation

       USCI_A_UART_enable(USCI_A0_BASE);

       //Enable Receive Interrupt

       USCI_A_UART_clearInterrupt(USCI_A0_BASE,USCI_A_UART_RECEIVE_INTERRUPT);

       USCI_A_UART_enableInterrupt(USCI_A0_BASE,USCI_A_UART_RECEIVE_INTERRUPT);

       __enable_interrupt();

}

 

#pragma vector=USCI_A0_VECTOR

__interrupt void USCI_A0_ISR(void)

{

   switch (__even_in_range(UCA0IV,4))

   {

       //Vector 2 - RXIFG

       case 2:

           //RxBuf[lengt++]=USCI_A_UART_receiveData(USCI_A0_BASE);

           RxBuf[lengt++]=UCA0RXBUF;

           break;

       default: break;

   }

}

 

int getTVOC()

{

   uint8_t check=0;

   for(lengt=0;lengt<9;lengt++)

   {

       RxBuf[lengt] = 0x00;

   }

   lengt = 0;

   UARTSend0(TVOCSend,9);

   mDelay(100);

   lengt = 0;

   if(RxBuf[0] == 0xFF)

   {

       int i;

       for(i=0;i<9;i++)

       {

           TVOCtest[i] = RxBuf[i];

           RxBuf[i] = 0x00;

       }

       if(CheckSum(TVOCtest) == true&&TVOCtest[1] == 0x86)

       {

           TVOC0=((TVOCtest[2]<<8)+TVOCtest[3]);      

           sprintf(TVOC,"%.2f",TVOC0);

           return true;

       }

       else

           return false;

   }

   else

       return false;

}