C-发送SMS GSM单击

Question

"我正在使用Mikroe的示例代码进行GSM单击，并使用几行代码来发送示例文本消息。但是我对'sendsmsmsg'有问题MSG是未申报标识符的功能。我试图在代码的顶部定义它，但仍然无法使用。

"这使用Mikroelektronika开发的GSM点击库"

/*
Example for GSM Click
    Date          : Jan 2018.
    Author        : MikroE Team
Test configuration PIC32 :
    MCU                : P32MX795F512L
    Dev. Board         : EasyPIC Fusion v7
    PIC32 Compiler ver : v4.0.0.0
---
Description :
The application is composed of three sections :
- System Initialization - Initializes all necessary GPIO pins, UART used for
the communcation with GSM module and UART used for infromation logging
- Application Initialization - Initializes driver, power on module and sends few
command for the default module configuration
- Application Task - running in parallel core state machine and checks for call flag. 
If call detected parser will hang up call.
Additional Functions :
All additional functions such as timer initialization and default handler. 
Notes :
- Echo must be turned off for succefull parsing. ( ATE0 )
- UART polling works much better with HFC enabled.
- In case of usage of other MCUs Timer initialization must be adjusted according to your MCU.
*/
#define __GSM__
#include "Click_GSM_types.h"
#include "Click_GSM_config.h"
#include "Click_GSM_timer.h"
#include <stdbool.h>
static uint8_t callFlag;
char uart2Buf;
bool rc;

void gsm_default_handler( uint8_t *rsp, uint8_t *evArgs )
{
    mikrobus_logWrite( rsp, _LOG_TEXT );
//  SKIP <CR> and <LF>
    if (0 == strncmp("RING", rsp + 2, 4))
    {
        callFlag = 1;
    }
}
void systemInit()    //initialize the mikrobus pins as GPIO and UART pins
{
    callFlag = 0;
    mikrobus_gpioInit( _MIKROBUS1, _MIKROBUS_AN_PIN, _GPIO_INPUT );              //enable AN pin as input
    mikrobus_gpioInit( _MIKROBUS1, _MIKROBUS_PWM_PIN, _GPIO_INPUT );             //enable PWM pin as input
    mikrobus_gpioInit( _MIKROBUS1, _MIKROBUS_INT_PIN, _GPIO_INPUT );             //enable INT pin as input
    mikrobus_gpioInit( _MIKROBUS1, _MIKROBUS_RST_PIN, _GPIO_OUTPUT );            //enable RST pin as output
    mikrobus_gpioInit( _MIKROBUS1, _MIKROBUS_CS_PIN, _GPIO_OUTPUT );             //enable CS pin as output
    mikrobus_uartInit( _MIKROBUS1, &_GSM_UART_CFG[0] );                          //enable UART communication
    mikrobus_logInit( _LOG_USBUART_B, 9600 );                                    //initialize the log with baud rate
}
void WriteString(char *strBuf)    //Write String
{
    while(strBuf)
    {
     UART2_Write(*strBuf++);
    }
    UART2_Write(0x0D);
}
void sendSMSmsg(char *msg)
{
    gsm_cmdSingle("AT+CMGS="[phone]"");   //dial it up
    WriteString(msg);                             //send the message
    UART2_Write(0x1A);                            //Ctrl-Z
    UART2_Write(0x0D);                            //CR
    rc = false;                                   //wait for OK
    do
    {
     if (UART2_Data_Ready()==1)
     {
         UART2_Read_Text(uart2Buf,"OK", 255);
         rc = true;
     }
    }while (rc==false);
}
void applicationInit()
{   char msg[];
// TIMER INIT
    gsm_configTimer();
// DRIVER INIT
    gsm_uartDriverInit((T_GSM_P)&_MIKROBUS1_GPIO, (T_GSM_P)&_MIKROBUS1_UART);
    gsm_coreInit( gsm_default_handler, 1500 );
// MODULE POWER ON
    gsm_hfcEnable( true );
    gsm_modulePower( true );
// MODULE INIT
    gsm_cmdSingle( "AT" );            //knock on the door
    gsm_cmdSingle( "AT" );
    gsm_cmdSingle( "AT" );
    gsm_cmdSingle( "ATE0" );          //turn off echo
    gsm_cmdSingle( "AT+CMGF=1" );     //text messaging
//SMS Message
   msg[0] = '';
   strcat(msg, "Test message 1");
   strcat(msg, "rn");               //add new line (CR+LF)
}

void applicationTask()
{
// CORE STATE MACHINE
    gsm_process();
    if (0 != callFlag)
    {
        gsm_cmdSingle( "ATH" );
        Delay_ms( 3000 );
        sendSMSmsg(msg);
        callFlag = 0;
    }
}
void main()
{
    systemInit();
    applicationInit();
    while (1)
    {
        applicationTask();
    }
}
/* ----------------------

"表达式中未宣布的标识符'msg'

Answer 1

您有此代码：

char msg[];
...
//SMS Message
msg[0] = '';
strcat(msg, "Test message 1");
strcat(msg, "rn");               //add new line (CR+LF)

第一行定义了指针：

char msg[];

随后的行在内存中随机写入并损坏它：

msg[0] = '';
strcat(msg, "Test message 1");
strcat(msg, "rn");               //add new line (CR+LF)

编写未分配记忆的结果是不确定的=任何可能发生，需要或不希望的，预期或意外的。

---

修复此操作后，您可以继续调试。