Getting AT commands in Configured mobile number

[Lucifer37]

Hi,

I'm using STM32H745ZI for 4G LTE Communication Quectel EC200U-CN to transmit message using UART in Asynchronous mode, if I send continuous message then I'm getting this ................

AT
AT+CPIN?
AT+CMGF=1
AT+CMGD=1,4
AT+CSCS="GSM"
AT+CSCA="919849087001",145
ATE0
AT+CPIN?
AT+CMGS="+917981134448"
Hello from GSM!!

int main()

{

/*All initialize of UART and stuff*/

send4GSMS("Hello from GSM!!");

}



void send4GSMS(uint8_t *string)
{
//Enter CTRL+Z after sending the data, then the message will be sent
unsigned char asciiValue = 0x1A;

//Command to send a short message from TE to network
    uint8_t sendMsg[30] = "AT+CMGS=\"+917981134448\"";          //Configured mobile number
//sends the message from TE to network
sendATCommand(sendMsg);
LL_mDelay(1);

// Send the data
while (*string != '\0') {
// Transmit one character at a time
LL_USART_TransmitData8(USART3, *string++);
// Wait until transmit is complete
while (!LL_USART_IsActiveFlag_TC(USART3));
// Clear the TC flag for the next byte transmission
LL_USART_ClearFlag_TC(USART3);
}
// Send carriage return and line feed
LL_USART_TransmitData8(USART3, CR);
while (!LL_USART_IsActiveFlag_TC(USART3));
LL_USART_TransmitData8(USART3, LF);
while (!LL_USART_IsActiveFlag_TC(USART3));
LL_USART_TransmitData8(USART3, asciiValue);
while (!LL_USART_IsActiveFlag_TC(USART3));

LL_mDelay(10);
}

void MX_USART3_UART_Init(void)
{
LL_USART_InitTypeDef USART_InitStruct = { 0 };
LL_GPIO_InitTypeDef GPIO_InitStruct = { 0 };

LL_RCC_SetUSARTClockSource(LL_RCC_USART234578_CLKSOURCE_PCLK1);

/* Peripheral clock enable */
LL_APB1_GRP1_EnableClock(LL_APB1_GRP1_PERIPH_USART3);

LL_AHB4_GRP1_EnableClock(LL_AHB4_GRP1_PERIPH_GPIOD);
/**USART3 GPIO Configuration
PD8   ------> USART3_TX
PD9   ------> USART3_RX
*/
GPIO_InitStruct.Pin = LL_GPIO_PIN_8 | LL_GPIO_PIN_9;
GPIO_InitStruct.Mode = LL_GPIO_MODE_ALTERNATE;
GPIO_InitStruct.Speed = LL_GPIO_SPEED_FREQ_LOW;
GPIO_InitStruct.OutputType = LL_GPIO_OUTPUT_PUSHPULL;
GPIO_InitStruct.Pull = LL_GPIO_PULL_NO;
GPIO_InitStruct.Alternate = LL_GPIO_AF_7;
LL_GPIO_Init(GPIOD, &GPIO_InitStruct);

/* USART3 interrupt Init */
NVIC_SetPriority(USART3_IRQn,
NVIC_EncodePriority(NVIC_GetPriorityGrouping(), 0, 0));
NVIC_EnableIRQ(USART3_IRQn);

USART_InitStruct.PrescalerValue = LL_USART_PRESCALER_DIV1;
USART_InitStruct.BaudRate = 115200;
USART_InitStruct.DataWidth = LL_USART_DATAWIDTH_8B;
USART_InitStruct.StopBits = LL_USART_STOPBITS_1;
USART_InitStruct.Parity = LL_USART_PARITY_NONE;
USART_InitStruct.TransferDirection = LL_USART_DIRECTION_TX_RX;
USART_InitStruct.HardwareFlowControl = LL_USART_HWCONTROL_NONE;
USART_InitStruct.OverSampling = LL_USART_OVERSAMPLING_16;
LL_USART_Init(USART3, &USART_InitStruct);

//    USART3->BRR = 0x35B;

LL_USART_SetTXFIFOThreshold(USART3, LL_USART_FIFOTHRESHOLD_1_8);
LL_USART_SetRXFIFOThreshold(USART3, LL_USART_FIFOTHRESHOLD_1_8);
LL_USART_DisableFIFO(USART3);
LL_USART_ConfigAsyncMode(USART3);

LL_USART_Enable(USART3);
/* Polling USART3 initialisation */
while ((!(LL_USART_IsActiveFlag_TEACK(USART3)))
|| (!(LL_USART_IsActiveFlag_REACK(USART3)))) {
}
/* Initializing the USART3 Receive Interrupt */
LL_USART_ReceiveData8(USART3);
LL_USART_EnableIT_RXNE_RXFNE(USART3);
}

void sendATCommand(const uint8_t *command)
{
// Clearing the rxBuffer before sending a new command
//(void) memset(&uart3_Buf, 0, sizeof(uart3_Buf));

// Send the command
while (*command != '\0') {
// Transmit one character at a time
LL_USART_TransmitData8(USART3, *command++);
// Wait until transmit is complete
while (!LL_USART_IsActiveFlag_TC(USART3));
// Clear the TC flag for the next byte transmission
LL_USART_ClearFlag_TC(USART3);
}

// Send carriage return and line feed
LL_USART_TransmitData8(USART3, CR);
while (!LL_USART_IsActiveFlag_TC(USART3));
LL_USART_TransmitData8(USART3, LF);
while (!LL_USART_IsActiveFlag_TC(USART3));

LL_mDelay(1);
}

[SofLit]

Hello,

This is not a STM32 question but it's related to the module you are using and the issue is not clear.

What do you mean by:

---

@Lucifer37 wrote:

if I send continuous message then I'm getting this ................

AT
AT+CPIN?
AT+CMGF=1
AT+CMGD=1,4
AT+CSCS="GSM"
AT+CSCA="919849087001",145
ATE0
AT+CPIN?
AT+CMGS="+917981134448"
Hello from GSM!!

---

What do you mean by "this"? the text in bold? is it an AT answer from the 4G modem?

[Andrew Neil]

---

@Lucifer37 wrote:

if I send continuous message

---

What do you mean by that?

You should never just send continuous AT commands - you must always wait for the reply to one command before sending the next.

---

@Lucifer37 wrote:

I'm using STM32H745ZI for 4G LTE Communication Quectel EC200U-CN

Please show your schematic.

See: How to write your question to maximize your chances to find a solution

[SofLit]

---

@Andrew Neil wrote:
you must always wait for the reply to one command before sending the next.

---

Indeed.

[Lucifer37]

@Andrew Neil 

Along with actual message "Hello from GSM!!" I'm getting AT commands in SMS

Actually I'm giving 10m sec delay sending any message via SMS, also I have given delays in AT commands, I increase the delays but still getting the AT commands along with the actual message.

[SofLit]

Hello,

Did you try to interface the module with a PC and send commands with hyperterminal and see if it responds correctly to the commands?

[Andrew Neil]

---

@Lucifer37 wrote:

Along with actual message "Hello from GSM!!" I'm getting AT commands in SMS

---

Still not at all clear what you mean.

Where, exactly, are you "getting" these commands?

"getting" suggests receiving - but normally you would be sending the commands.

A diagram could be clearer; eg,

Microcontroller
(STM32)                                 Quectel
+-------------+                        +-------------+
|             |     SEND commands      |             |
|          TX +----------------------->+ RX          |
|             |                        |             |
|          RX +<-----------------------+ TX          |
|             |    RECEIVE responses   |             |
+-------------+                        +-------------+

(See this for how to post such a "text-diagram", or upload a picture, or your schematics)

---

@Lucifer37 wrote:

I have given delays in AT commands, I increase the delays but still getting the AT commands along with the actual message.

---

Again, that's doomed to failure: you must to pay attention to the replies - not just rely blindly on arbitrary delays!

This is probably the commonest mistake people make with AT Commands:

https://www.avrfreaks.net/s/topic/a5C3l000000UYXnEAO/t146581?comment=P-1400752