Wake on motion in nrf52

RE: Wake on motion in nrf52

Jørgen Holmefjord — Thu, 09 Mar 2017 10:12:22 GMT

Great that you got it working!

RE: Wake on motion in nrf52

Swapnil — Thu, 09 Mar 2017 09:58:06 GMT

Thank you Jorgen for help, I have solved the problem of wake on motion functionality. Apparently I was doing double configuration for interrupt in MPU initialization and in MPU_wake on motion functionality. when excluded interrupt initialization from MPU_init function, it started to work fine. But thank you so much for help

RE: Wake on motion in nrf52

Swapnil — Wed, 08 Mar 2017 12:55:12 GMT

I tried to change last write

// Enable Cycle Mode (Accel Low Power Mode) //In PWR_MGMT_1 (0x6B) make CYCLE =1

err_code[7] = i2c_write_registers(I2C_MPU9250_ADDR, MPU_REG_PWR_MGMT_1, 0x20);

but no effect, still no interrupt.

RE: Wake on motion in nrf52

Jørgen Holmefjord — Wed, 08 Mar 2017 12:50:02 GMT

According to the MPU-9250 Register Map and Descriptions document, CYCLE should be bit 5 of PWR_MGMT_1 register. Can you try changing last write to 0x20?

RE: Wake on motion in nrf52

Swapnil — Wed, 08 Mar 2017 12:32:46 GMT

Sorry for confusion but I changed it and I am using below configuration

uint32_t MPU6500_StartMotionDetection(void)

{

uint32_t err_code[CONFIGURATION_CHECK_LENGTH];


//*********************************************************************************//
// Make sure accelerometer is running
//In PWR_MGMT_1 (0x6B) make CYCLE = 0, SLEEP = 0 and STANDBY = 0
err_code[0] = i2c_write_registers(I2C_MPU9250_ADDR, MPU_REG_PWR_MGMT_1, 0x00);

//Set DIS_XA, DIS_YA, DIS_ZA = 0 and DIS_XG, DIS_YG, DIS_ZG = 1
err_code[1] = i2c_write_registers(I2C_MPU9250_ADDR, MPU_REG_PWR_MGMT_2, 0x07);

// Set Accel LPF setting to 184 Hz Bandwidth
//ACCEL_CONFIG 2 (0x1D) set ACCEL_FCHOICE_B = 1 and A_DLPFCFG[2:]=1(b001)
err_code[2] = i2c_write_registers(I2C_MPU9250_ADDR, MPU_REG_ACCEL_CONFIG_2, 0x05);

// Enable Motion Interrupt
err_code[3] = i2c_write_registers(I2C_MPU9250_ADDR, MPU_REG_INT_ENABLE, 0x40);

// Enable Accel Hardware Intelligence
//In MOT_DETECT_CTRL (0x69), set ACCEL_INTEL_EN = 1 and ACCEL_INTEL_MODE = 1
err_code[4] = i2c_write_registers(I2C_MPU9250_ADDR, MPU_REG_MOT_DETECT_CTRL, 0xC0);

// Set Motion Threshold
//In WOM_THR (0x1F), set the WOM_Threshold[7:0] to 1~255 LSBs (0~1020mg)
err_code[5] = i2c_write_registers(I2C_MPU9250_ADDR, MPU_REG_WOM_THR, 0xFF);

// Set Frequency of Wake-up
//In LP_ACCEL_ODR (0x1E), set Lposc_clksel[3:0] = 0.24Hz ~ 500Hz
err_code[6] = i2c_write_registers(I2C_MPU9250_ADDR, MPU_REG_LP_ACCEL_ODR, 0x03);

// Enable Cycle Mode (Accel Low Power Mode)
//In PWR_MGMT_1 (0x6B) make CYCLE =1
err_code[7] = i2c_write_registers(I2C_MPU9250_ADDR, MPU_REG_PWR_MGMT_1, 0x03);
//*********************************************************************************//

}

RE: Wake on motion in nrf52

Jørgen Holmefjord — Wed, 08 Mar 2017 12:30:54 GMT

It does not look like it to me. For instance this line from the link: writeI2C_1Byte(MPU9250_DEFAULT_ADDRESS, MPU9250_ACCEL_CONFIG2, 0b00000101) does not look like the same as the line i2c_write_registers(I2C_MPU9250_ADDR, MPU_REG_ACCEL_CONFIG_2, 0x01) from your code (0b00000101 and 0x01 is not the same value).

RE: Wake on motion in nrf52

Swapnil — Wed, 08 Mar 2017 12:09:44 GMT

No i kept the exact same values

RE: Wake on motion in nrf52

Jørgen Holmefjord — Wed, 08 Mar 2017 12:08:34 GMT

But you changed the values? Are you doing a different configuration than the link?

RE: Wake on motion in nrf52

Swapnil — Wed, 08 Mar 2017 12:03:13 GMT

Yes I took reference from below link link text

RE: Wake on motion in nrf52

Jørgen Holmefjord — Wed, 08 Mar 2017 12:01:45 GMT

Are you sure that your configuration of the Wake-on-motion is correct?

RE: Wake on motion in nrf52

Swapnil — Wed, 08 Mar 2017 11:19:06 GMT

Hello Jorgen, Thank you for suggestion. I checked the voltage levels at interrupt pin and i noticed that from the moment I flash the program inside I see the voltage at interrupt pin is 1.1V and then it goes to 1mV and remain constant but if I dont configure the motion detect functionality then I saw the voltage level of 1.1V and remains constant.

RE: Wake on motion in nrf52

Jørgen Holmefjord — Wed, 08 Mar 2017 10:15:35 GMT

Do you have an oscilloscope? You could also try with a multimeter, but it will depend on how long the signal is set and how acurate your meter is if you are able to measure the signal. Alternatively, you can connect the line to another board running the pin_change_interrupt example, to see if it detects the pin once the MPU is initialized.

RE: Wake on motion in nrf52

Swapnil — Tue, 07 Mar 2017 13:23:14 GMT

I dont have logic analyzer to test it now, hence its not possible to check any interrupt line. Can you suggest some other option for detecting?

RE: Wake on motion in nrf52

Jørgen Holmefjord — Tue, 07 Mar 2017 09:19:38 GMT

Have you checked the interrupt line from your MPU9250 with a logic analyzer, to see if it is sending a singal when it detects motion?

RE: Wake on motion in nrf52

Swapnil — Tue, 07 Mar 2017 09:10:27 GMT

I was getting getting error code 8, but after connecting interrupt pin from pin no. 38 to pin 22, the error is not there. But I am not getting wake on motion effect.

RE: Wake on motion in nrf52

Jørgen Holmefjord — Mon, 06 Mar 2017 09:35:32 GMT

Your initialization looks similar to the one described in the GPIOTE driver documentation. What error code are you getting?