How to send sensor data using AT commands to a device using Uart in segger embedded studio

[Rajbir Singh]

Hi, I am new to NRF and segger embedded studio.

So I want to send temperature sensor data connected with nrf52840 DK to the Murata1_SC  device using UART.

The data will be sent using AT Commands.

So how to send AT Commands in Segger embedded studio.

Thank you for the help in advance.

[Rajbir Singh]

#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include "app_uart.h"
#include "app_error.h"
#include "nrf_delay.h"
#include "nrf.h"
#include "bsp.h"
#include "nrf_uart.h"

#define UART_TX_BUFF_SIZE 128
#define UART_RX_BUFF_SIZE 128

#define UART_HWFC APP_UART_FLOW_CONTROL_DISABLED

void uart_err_handle(app_uart_evt_type_t * p)
{
  

}

int main(void)
{
  uint32_t err_code;

  bsp_board_init(BSP_INIT_LEDS);
  
  const app_uart_comm_params_t com_params = 
   {
    RX_PIN_NUMBER,
    TX_PIN_NUMBER,
    RTS_PIN_NUMBER,
    CTS_PIN_NUMBER,
    UART_HWFC,
    false,
    NRF_UART_BAUDRATE_115200
    };

  APP_UART_FIFO_INIT(&com_params, UART_RX_BUFF_SIZE, UART_TX_BUFF_SIZE, uart_err_handle, APP_IRQ_PRIORITY_LOWEST, err_code);

  APP_ERROR_CHECK(err_code);
  
  printf("Hello PC from Nordic Device!!!\r\n");
  
  while(true)
  {
    uint8_t cr;

    while(app_uart_get(&cr) != NRF_SUCCESS);//wait here for the character from pc
    if(cr == 'o')
    {
      bsp_board_leds_on();
      printf("Leds are ON\r\n");
    }
    if(cr == 'f')
    {
      bsp_board_leds_off();
      printf("Leds are OFF\r\n");
    }
  }
}

[Rajbir Singh]

I have seen this code

uart_putstring((uint8_t*)"AT\r");
nrf_delay_ms(2000);
uart_putstring((uint8_t*)"AT+CMGF=1\r");
       nrf_delay_ms(2000);
uart_putstring((uint8_t*)"AT+CMGS=\"8919242248\"\r");
   nrf_delay_ms(2000);
   uart_putstring((uint8_t*)"test\r");
          nrf_delay_ms(2000);
          app_uart_put((char)0x1A);   ///used (uint8_t) 26 also but no response..
                 nrf_delay_ms(1000);

in this link, where someone is saying to wait for the response, so how can i do that.

[Rajbir Singh]

I am using hardware pins,but i am able to make communication with device.

[Rajbir Singh]

Hi awneil by using the above code, I am not able to send anything.

But I tried the following code to send data to Arduino and I am able to send the data.

#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include "app_uart.h"
#include "app_error.h"
#include "nrf_delay.h"
#include "nrf.h"
#include "bsp.h"
#include "nrf_uart.h"

//#define RX_PIN_NUMBER 27 //8
//#define TX_PIN_NUMBER 26 //6
//#define CTS_PIN_NUMBER 12 //7
//#define RTS_PIN_NUMBER 11 //5


#define UART_TX_BUFF_SIZE 256
#define UART_RX_BUFF_SIZE 256

#define UART_HWFC APP_UART_FLOW_CONTROL_DISABLED

void uart_err_handle(app_uart_evt_type_t * p)
{
  

}

int main(void)
{
  uint32_t err_code;

  bsp_board_init(BSP_INIT_LEDS);
  
  const app_uart_comm_params_t com_params = 
   {
    RX_PIN_NUMBER,
    TX_PIN_NUMBER,
    RTS_PIN_NUMBER,
    CTS_PIN_NUMBER,
    UART_HWFC,
    false,
    NRF_UART_BAUDRATE_115200
    };

  APP_UART_FIFO_INIT(&com_params, UART_RX_BUFF_SIZE, UART_TX_BUFF_SIZE, uart_err_handle, APP_IRQ_PRIORITY_LOWEST, err_code);

  APP_ERROR_CHECK(err_code);
  
  printf("Hello PC from Nordic\r\n");
  
  while(true)
  {
    uint8_t cr;

    while(app_uart_get(&cr) != NRF_SUCCESS);//wait here for the character from pc
    if(cr == 'OK')
    {
      bsp_board_leds_on();
      printf("Leds are ON\r\n");
    }
    if(cr == 'ERROR')
    {
      bsp_board_leds_off();
      printf("Leds are OFF\r\n");
    }
  }
}

 

Also, I am confused that by changing these pins

#define RX_PIN_NUMBER 27 //8
#define TX_PIN_NUMBER 26 //6
#define CTS_PIN_NUMBER 12 //7
#define RTS_PIN_NUMBER 11 //5

Could I able to change the hardware UART to Software UART

Because Hardware UART is used by Debugger 

[Rajbir Singh]

Please help i have some issues.

[Hung Bui]

Hi,

What's the exact issue you are having ? 
Can you develop your app based on the uart example in the SDK or the example that you found working above ? 

I don't really understand what you meant by Software UART ? 

What did you mean by "hardware UART is used by debugger" ? 
Calling this: 

#define RX_PIN_NUMBER 27 //8
#define TX_PIN_NUMBER 26 //6
#define CTS_PIN_NUMBER 12 //7
#define RTS_PIN_NUMBER 11 //5

Will degine the RX pin to pin P0.27 on the chip. TX pin to P0.26 on the chip, and so on. 

[awneil]

Hung Bui said:

don't really understand what you meant by Software UART

I presume he means bit-banging it in software?

Doesn't seem much point in doing that when the nRF52840 has 2 "real" (ie, hardware) UARTS?

Hung Bui said:

RX pin to pin P0.27 on the chip. TX pin to P0.26

How does it work for P1.xx pins ?