NRF528540 with MPU9255 Problem

[kyle.ng1]

Hello guys, i currently applying the example about MPU9255 following this:GitHub - Martinsbl/nrf5-mpu-examples

i'm using the app_mpu.c, app_mpu.h, mpu9255_register_map.h, nrf_drv_mpu.h, nrf_drv_mpu_twi.c to create new project with the main.c and sdk config in nrf5-mpu-simple. 

when i build and log showing this error. Could anyone help me with this, many thank,

Kyle. 

[Edvin]

Hello,

Line 35 in main.c in the nrf5-mpu-simple application is just a comment, so obviously you did some modifications, at least removed the comments on the top. 

What function returned the error 13 that was passed into your APP_ERROR_CHECK(err_code) in main.c on line 35?

Are you using Keil? Did you add the preprocessor definitions MPU9255 and MPU_USES_TWI to your project settings, according to the readme file in the github repository that you linked to?

Best regards,

Edvin

[kyle.ng1]

Hello Edvin, 

The line 35 in my main.c is ret_code = app_mpu_config(&p_mpu_config); // Configure the MPU with above values

The function that return error 13 is the mpu_init function.

I'm using segger embedded studio but i'm already add the preprocessor definitions MPU9255 and MPU_USES_TWI.

Best regards,

Kyle

[Edvin]

Hello,

Can you please send me the main.c file (your latest version) with the corresponding error log. The log would not say what it says if your line 35 is ret_code_t = app_mpu_config(...).

mpu_init() doesn't return any parameters (at least not in the unmodified nrf5-mpu-init\main.c file). 

But I guess it is app_mpu_config() that returns 13, then. If that is the case, it looks like the nrf_drv_mpu_write_registers() returns NRF_ERROR_TIMEOUT, meaning that nrf_drv_twi_xfer() doesn't receive a callback. Is the MPU powered? Have you tried to analyze the TWI pins using a logic analyzer? Is the TWI data sent from the nRF? And does the MPU reply over TWI?

Best regards,

Edvin

[kyle.ng1]

Hello, 

This is my main.c file 

Fullscreen 7506.main.c Download

 /* 
  * This example is not extensively tested and only 
  * meant as a simple explanation and for inspiration. 
  * NO WARRANTY of ANY KIND is provided. 
  */

#include <stdio.h>
#include "boards.h"
#include "app_uart.h"
#include "app_error.h"
#include "nrf_delay.h"
#include "app_mpu.h"

#include "nrf_log.h"
#include "nrf_log_ctrl.h"
#include "nrf_log_default_backends.h"


/**@brief Function for initializing the nrf log module.
 */
static void log_init(void)
{
    ret_code_t err_code = NRF_LOG_INIT(NULL);
    APP_ERROR_CHECK(err_code);

    NRF_LOG_DEFAULT_BACKENDS_INIT();
}


void mpu_init(void)
{
    ret_code_t ret_code;
    // Initiate MPU driver
    ret_code = app_mpu_init();
    APP_ERROR_CHECK(ret_code); // Check for errors in return value
    
    // Setup and configure the MPU with intial values
    app_mpu_config_t p_mpu_config = MPU_DEFAULT_CONFIG(); // Load default values
    p_mpu_config.smplrt_div = 19;   // Change sampelrate. Sample Rate = Gyroscope Output Rate / (1 + SMPLRT_DIV). 19 gives a sample rate of 50Hz
    p_mpu_config.accel_config.afs_sel = AFS_2G; // Set accelerometer full scale range to 2G
    ret_code = app_mpu_config(&p_mpu_config); // Configure the MPU with above values
    APP_ERROR_CHECK(ret_code); // Check for errors in return value 
}

/**
 * @brief Function for main application entry.
 */
int main(void)
{    
    uint32_t err_code;
    
    // Initialize.
    log_init();
	NRF_LOG_INFO("\033[2J\033[;H"); // Clear screen
    
    mpu_init();
    
    // Start execution.
    NRF_LOG_INFO("MPU Free Fall Interrupt example.");
    
    accel_values_t acc_values;
    uint32_t sample_number = 0;
    
    while(1)
    {
        if(NRF_LOG_PROCESS() == false)
        {
            // Read accelerometer sensor values
            err_code = app_mpu_read_accel(&acc_values);
            APP_ERROR_CHECK(err_code);
            // Clear terminal and print values
            NRF_LOG_INFO("\033[3;1HSample # %d\r\nX: %06d\r\nY: %06d\r\nZ: %06d", ++sample_number, acc_values.x, acc_values.y, acc_values.z);
            nrf_delay_ms(250);
        }
    }
}

/** @} */

 

The MPU was powered and i have built 1 project before to test the response of TWI it's work normally, but the init of MPU is fail, idk why?

 

Best regards,

Kyle

[Edvin]

Hello Kyle,

kyle.ng1 said:

i have built 1 project before to test the response of TWI it's work normally,

Does the TWI from the nRF work normally, or does the TWI on the MPU work normally?

The screenshot of the log in your last reply, is that from the SDK\examples\peripheral\twi_scanner example, or is it from your nrf5-mpu-simple application?

Either way, it suggests that no TWI devices are connected correctly. At least not that the nRF can see.

Did you try to analyze the TWI bus using a logic analyzer? Does the MPU send a reply?

BR,
Edvin

[kyle.ng1]

Hello Edvin, 

I have changed the pin out of SDA and SCL it worked normally thank for your support

Best Regard,

Kyle.