C 从GPS模块读取UART接收缓冲器时，程序挂起

这是在我为我的capstone项目设计的定制PCB上，我仍然对此感到困惑，因为不幸的是，我没有很多UART的经验。我确信这就是问题所在，我只发现讨论主要围绕arduino用户等，而不是C编程/UART通信

我的程序使其进入并读取U3STAbits.URXDA true（缓冲区已满），但它不会继续超过该点，并且在尝试读取U3RXREG后不会转到该行

我使用的是PIC24FJ512GA606微控制器和MPLAB X IDE，我没有任何外设库

我试图与之通信的GPS模块是Antenova M20048，当我在模式寄存器下启用UARTEN时，备用引脚变高

到目前为止，我的模块没有收到任何响应，我没有办法在家里探测它，看看它是否真的有响应，缓冲区被标记为已满的事实给了我希望它一切正常，如果有人有任何想法，也许我只是遗漏了一些东西

#define FCY 8000000    //required for __delay_us(time) function
#include "elen116header.h"
#include <libpic30.h>
#include <stdint.h>
#include <math.h>
#include <string.h>



int main(void)
{

    UART2_Initialize();
    UART3_Initialize();
   __delay_ms(250);
   __delay_ms(250);
   printf("LoRa Tranciever Unit Online\n") ;
   
   char c='0'; //declare a character
   char data[80] = {'\0'};  //declare a character array to store an entire message
   int count = 80; //declare an integer to be used as an index variable
   
  __delay_ms(250);
  __delay_ms(250);
  
   //transmit the command to GPS
   strcpy(data,"$PMTK414*33\r\n");
   printf(" Sending: ");
   int i;
   count = 80;
   for(i = 0; i < count; i++)
   {
       c = data[i];
       
       if(c == '\0' )
       {
           memset(data, '\0', sizeof(char) * 80);//clear data
           i = count;
       }
       else
       {
           UART3_Write(c);
           printf("%c", c);
       }
   }
   printf("\n\n Reading: ");
    
//transmission of command is finished, now read in characters
while(1) //forever read in and store the last NMEA message
{
        if(U3STAbits.OERR) //check to see if there's an overrun error
            U3STAbits.OERR = 0;//clear to allow messages to be received
        if(U3STAbits.URXDA) //check if data is ready to be read
        {
        printf("read attempt ");
        c = U3RXREG; //get a character from the receive buffer
        printf("%c", c);
        while(!(U3STAbits.URXDA == 1));
     if(c == '$') //c == $, hex=0x0024
        {
        count = 0; //for indexing the character array
        }
     if(count < 80)
        {
        data[count] = c;//store the character into the data array
        count++; //increment the index
        }
    }
}

   return 0;
}

#定义uu delay u us（时间）功能所需的FCY 8000000//
#包括“elen116头.h”
#包括
#包括
#包括
#包括
内部主（空）
{
UART2_初始化（）；
UART3_初始化（）；
__延迟时间（250）；
__延迟时间（250）；
printf（“联机LoRa分期付款单位”）；
char c='0'；//声明一个字符
char data[80]={'\0'}；//声明一个字符数组来存储整个消息
int count=80；//声明一个用作索引变量的整数
__延迟时间（250）；
__延迟时间（250）；
//将命令发送到GPS
strcpy（数据，“$PMTK414*33\r\n”）；
printf（“发送：”）；
int i；
计数=80；
对于（i=0；i

以及具有一些配置位和UART配置的报头

// PIC24FJ512GA606 Configuration Bit Settings

// 'C' source line config statements

// FSEC
#pragma config BWRP = OFF               // Boot Segment Write-Protect bit (Boot Segment may be written)
#pragma config BSS = DISABLED           // Boot Segment Code-Protect Level bits (No Protection (other than BWRP))
#pragma config BSEN = OFF               // Boot Segment Control bit (No Boot Segment)
#pragma config GWRP = OFF               // General Segment Write-Protect bit (General Segment may be written)
#pragma config GSS = DISABLED           // General Segment Code-Protect Level bits (No Protection (other than GWRP))
#pragma config CWRP = OFF               // Configuration Segment Write-Protect bit (Configuration Segment may be written)
#pragma config CSS = DISABLED           // Configuration Segment Code-Protect Level bits (No Protection (other than CWRP))
#pragma config AIVTDIS = OFF            // Alternate Interrupt Vector Table bit (Disabled AIVT)

// FBSLIM
#pragma config BSLIM = 0x1FFF           // Boot Segment Flash Page Address Limit bits (Boot Segment Flash page address  limit)

// FSIGN

// FOSCSEL
#pragma config FNOSC = FRC              // Oscillator Source Selection (Internal Fast RC (FRC))
#pragma config PLLMODE = DISABLED       // PLL Mode Selection (No PLL used; PLLEN bit is not available)
#pragma config IESO = ON                // Two-speed Oscillator Start-up Enable bit (Start up device with FRC, then switch to user-selected oscillator source)

// FOSC
#pragma config POSCMD = NONE            // Primary Oscillator Mode Select bits (Primary Oscillator disabled)
#pragma config OSCIOFCN = OFF           // OSC2 Pin Function bit (OSC2 is clock output)
#pragma config SOSCSEL = ON             // SOSC Power Selection Configuration bits (SOSC is used in crystal (SOSCI/SOSCO) mode)
#pragma config PLLSS = PLL_PRI          // PLL Secondary Selection Configuration bit (PLL is fed by the Primary oscillator)
#pragma config IOL1WAY = OFF             // Peripheral pin select configuration bit (Allow only one reconfiguration)
#pragma config FCKSM = CSDCMD           // Clock Switching Mode bits (Both Clock switching and Fail-safe Clock Monitor are disabled)

// FWDT
#pragma config WDTPS = PS32768          // Watchdog Timer Postscaler bits (1:32,768)
#pragma config FWPSA = PR128            // Watchdog Timer Prescaler bit (1:128)
#pragma config FWDTEN = OFF              // Watchdog Timer Enable bits (WDT Enabled)
#pragma config WINDIS = OFF             // Watchdog Timer Window Enable bit (Watchdog Timer in Non-Window mode)
#pragma config WDTWIN = WIN25           // Watchdog Timer Window Select bits (WDT Window is 25% of WDT period)
#pragma config WDTCMX = WDTCLK          // WDT MUX Source Select bits (WDT clock source is determined by the WDTCLK Configuration bits)
#pragma config WDTCLK = LPRC            // WDT Clock Source Select bits (WDT uses LPRC)

// FPOR
#pragma config BOREN = ON               // Brown Out Enable bit (Brown Out Enable Bit)
#pragma config LPCFG = OFF              // Low power regulator control (No Retention Sleep)
#pragma config DNVPEN = ENABLE          // Downside Voltage Protection Enable bit (Downside protection enabled using ZPBOR when BOR is inactive)

// FICD
#pragma config ICS = PGD2               // ICD Communication Channel Select bits (Communicate on PGEC1 and PGED1)
#pragma config JTAGEN = OFF             // JTAG Enable bit (JTAG is disabled)
#pragma config BTSWP = OFF              // BOOTSWP Disable (BOOTSWP instruction disabled)

// FDEVOPT1
#pragma config ALTCMPI = DISABLE        // Alternate Comparator Input Enable bit (C1INC, C2INC, and C3INC are on their standard pin locations)
#pragma config TMPRPIN = OFF            // Tamper Pin Enable bit (TMPRN pin function is disabled)
#pragma config SOSCHP = ON              // SOSC High Power Enable bit (valid only when SOSCSEL = 1 (Enable SOSC high power mode (default))
#pragma config ALTVREF = ALTREFEN       // Alternate Voltage Reference Location Enable bit (VREF+ and CVREF+ on RA10, VREF- and CVREF- on RA9)

// #pragma config statements should precede project file includes.

/************************* DO NOT Alter any of the above code *******/
/************************* START of Your Program *********************/

            /***** Directives and Define AREA************/
#include <xc.h>
#include <stdio.h>
           

///////////////////////////////////////
// UART2
///////////////////////////////////////

void UART2_Initialize(void)
{
    
    /****************************************************************************
     * Set the PPS
     ***************************************************************************/
    __builtin_write_OSCCONL(OSCCON & 0xbf); // unlock PPS

    RPOR11bits.RP23R = 0x0005;    //RP23/RD1->UART2:U2TX
    RPINR19bits.U2RXR = 0x0018;    //RP24/RD2->UART2:U2RX

    __builtin_write_OSCCONL(OSCCON | 0x40); // lock PPS
    
/**    
     Set the UART2 module to the options selected in the user interface.
     Make sure to set LAT bit corresponding to TxPin as high before UART initialization
*/
    // STSEL 1; IREN disabled; PDSEL 8N; UARTEN enabled; RTSMD disabled; USIDL disabled; WAKE disabled; ABAUD disabled; LPBACK disabled; BRGH enabled; URXINV disabled; UEN TX_RX; 
    // Data Bits = 8; Parity = None; Stop Bits = 1;
    U2MODE = (0x8008 & ~(1<<15));  // disabling UARTEN bit
    // UTXISEL0 TX_ONE_CHAR; UTXINV disabled; URXEN disabled; OERR NO_ERROR_cleared; URXISEL RX_ONE_CHAR; UTXBRK COMPLETED; UTXEN disabled; ADDEN disabled; 
    U2STA = 0x00;
    // BaudRate = 9600; Frequency = 8000000 Hz; U2BRG 0x67; 
    U2BRG = 0x67;//0x33;
    // BaudRate = 57600; Frequency = 8000000 Hz; U2BRG 0x16; 
    //U2BRG = 0x16;//0x33;
    // BaudRate = 115200; Frequency = 8000000 Hz; U2BRG 0x16; 
    //U2BRG = 0x07;//0x33;
    
    // ADMADDR 0; ADMMASK 0; 
    U2ADMD = 0x00;
    
    UART2_Enable();  // enabling UARTEN bit
}

uint8_t UART2_Read(void)
{
    while(!(U2STAbits.URXDA == 1))
    {
        
    }

    if ((U2STAbits.OERR == 1))
    {
        U2STAbits.OERR = 0;
    }
    
    return U2RXREG;
}

void UART2_Write(uint8_t txData)
{
    while(U2STAbits.UTXBF == 1)
    {
        
    }

    U2TXREG = txData;    // Write the data byte to the USART.
}

uint16_t UART2_StatusGet (void)
{
    return U2STA;
}

void UART2_Enable(void)
{
    U2MODEbits.UARTEN = 1;
    U2STAbits.UTXEN = 1;
}

void UART2_Disable(void)
{
    U2MODEbits.UARTEN = 0;
    U2STAbits.UTXEN = 0;
}

///////////////////////////////////////
// UART3
///////////////////////////////////////


void UART3_Initialize(void)
{
    
    /****************************************************************************
     * Set the PPS
     ***************************************************************************/
    __builtin_write_OSCCONL(OSCCON & 0xbf); // unlock PPS

    RPOR4bits.RP9R = 0x0013;    //RP9/RB9>UART3:U3TX
    RPINR17bits.U3RXR = 0x0008;    //RP8/RB8->UART3:U3RX

    __builtin_write_OSCCONL(OSCCON | 0x40); // lock PPS
    ANSBbits.ANSB10 = 0;
    TRISBbits.TRISB10 = 0;
/**    
     Set the UART3 module to the options selected in the user interface.
     Make sure to set LAT bit corresponding to TxPin as high before UART initialization
*/
    // STSEL 1; IREN disabled; PDSEL 8N; UARTEN enabled; RTSMD disabled; USIDL disabled; WAKE disabled; ABAUD disabled; LPBACK disabled; BRGH disabled; URXINV disabled; UEN TX_RX; 
    // Data Bits = 8; Parity = None; Stop Bits = 1;
    U3MODE =  (0x8000 & ~(1 << 15));  // disabling UARTEN bit //
 
    // UTXISEL0 TX_ONE_CHAR; UTXINV disabled; URXEN disabled; OERR NO_ERROR_cleared; URXISEL RX_ONE_CHAR; UTXBRK COMPLETED; UTXEN disabled; ADDEN disabled; 
    U3STA = 0x00;
    // BaudRate = 9600; Frequency = 8000000 Hz; U2BRG 25; 
    U3BRG = 25;//0x33;
    // BaudRate = 57600; Frequency = 8000000 Hz; U2BRG 0x16; 
    //U3BRG = 0x16;//0x33;
    // BaudRate = 115200; Frequency = 8000000 Hz; U2BRG 0x16; 
    //U3BRG = 0x07;//0x33;
    
    // ADMADDR 0; ADMMASK 0; 
    U3ADMD = 0x00;
    
    UART3_Enable();  // enabling UARTEN bit
}

uint8_t UART3_Read(void)
{
   // while(!(U3STAbits.URXDA == 1)) //These are used in the program instead
    //{}

  //  if ((U3STAbits.OERR == 1))
   // {
   //     U3STAbits.OERR = 0;
   // }
    
    return U3RXREG;
}

void UART3_Write(uint8_t txData)
{
    while(U3STAbits.UTXBF == 1)
    {
        
    }

    U3TXREG = txData;    // Write the data byte to the USART.
}

uint16_t UART3_StatusGet (void)
{
    return U3STA;
}

void UART3_Enable(void)
{
    U3MODEbits.UARTEN = 1;
    U3STAbits.UTXEN = 1;
    U3STAbits.URXEN = 1;
    PORTBbits.RB10 = 1; //disable standby
}

void UART3_Disable(void)
{
    U3MODEbits.UARTEN = 0;
    U3STAbits.UTXEN = 0;
    U3STAbits.URXEN = 0;
}

//////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////

//helper function for std output functions

int __attribute__((__section__(".libc.write"))) write(int handle, void *buffer, unsigned int len) {
    int i;
    //UART2_Initialize();
    while(U2STAbits.TRMT == 0);  
    for (i = len; i; --i)
    {
        while(U2STAbits.TRMT == 0);
        U2TXREG = *(char*)buffer++;        
    }
    return(len);
}
//helper function for std intput functions
int __attribute__((__section__(".libc.read"))) read(int handle, void *buffer, unsigned int len) {
    int i;
    //UART2_Initialize();
    while(U2STAbits.URXDA == 0);  
    for (i = len; i; --i)
    {
        while(U2STAbits.URXDA == 0);
        *(char*)buffer++=U2RXREG;        
    }
    return(len);
}

//PIC24FJ512GA606配置位设置
//“C”源代码行配置语句
//FSEC
#pragma config BWRP=OFF//引导段写保护位（可以写入引导段）
#pragma config BSS=禁用//引导段代码保护级别位（无保护（BWRP除外））
#pragma config BSEN=OFF//引导段控制位（无引导段）
#pragma config GWRP=OFF//通用段写保护位（可以写入通用段）
#pragma config GSS=禁用//通用段代码保护级别位（无保护（GWRP除外））
#pragma config CWRP=OFF//配置段写保护位（配置段可能被写入）
#pragma config CSS=禁用//配置段代码保护级别位（无保护（CWRP除外））
#pragma config AIVTDIS=OFF//备用中断向量表位（禁用AIVT）
//FBSLIM
#pragma config BSLIM=0x1ff//引导段闪存页地址限制位（引导段闪存页地址限制）
//F标志
//福塞尔
#pragma config FNOSC=FRC//振荡器源选择（内部快速RC（FRC））
#pragma config PLLMODE=禁用//PLL模式选择（未使用PLL；PLLEN位不可用）
#pragma config IESO=ON//双速振荡器启动启用位（使用FRC启动设备，然后切换到用户选择的振荡器源）
//FOSC
#pragma config POSCMD=NONE//主振荡器模式选择位（主振荡器禁用）
#pragma config OSCIOFCN=OFF//OSC2引脚功能位（OSC2为时钟输出）
#pragma config SOSCSEL=ON//SOSC电源选择配置位（SOSC用于晶体（SOSCI/SOSCO）模式）
#pragma config PLLSS=PLL_PRI//PLL二次选择配置位（PLL由主振荡器馈电）
#pragma config IOL1WAY=OFF//外围引脚选择配置位（仅允许一次重新配置）
#pragma config FCKSM=CSDCMD//时钟切换模式位（时钟切换和故障安全时钟监视器均被禁用）
//FWDT
#pragma-config-WDTPS=PS32768//看门狗定时器后置定标器位（1:32768）
#pragma config FWPSA=PR128//看门狗定时器预分频器位（1:128）
#pragma config FWDTEN=OFF//看门狗定时器启用位（WDT启用）
#pragma config WINDIS=OFF//看门狗定时器窗口启用位（非窗口模式下的看门狗定时器）
#pragma config WDTWIN=WIN25//看门狗定时器窗口选择位（WDT窗口为WDT周期的25%）
#pragma config WDTCMX=WDTCLK//WDT MUX源选择位（WDT时钟源由WDTCLK配置位确定）
#pragma config WDTCLK=LPRC//WDT时钟源选择位（WDT使用LPRC）
//FPOR
#pragma config BOREN=ON//Brown Out启用位（Brown Out启用位）
#pragma config LPCFG=关闭//低功率调节器控制（无保留睡眠）
#pragma config DNVPEN=启用