How to wire I2C for NRF 51822 with MPU 9250.What SDK should I use?

RE: How to wire I2C for NRF 51822 with MPU 9250.What SDK should I use?

vohra alihussain — Mon, 09 Jul 2018 05:06:35 GMT

hello sigurd,

I am not able to see the data of mpu on my nrf tool box app...is that need any configuration..

the data is available on putty...

but I want it on the phone

RE: How to wire I2C for NRF 51822 with MPU 9250.What SDK should I use?

Sigurd — Tue, 03 Oct 2017 08:18:42 GMT

Have you seen the tutorials on this page ? I recommend the tutorials under "Bluetooth low energy", they will teach you how to create services and characteristics.

RE: How to wire I2C for NRF 51822 with MPU 9250.What SDK should I use?

priya — Tue, 26 Sep 2017 15:55:43 GMT

Could you please help me with how to do it? I don't which function is outputting the 'value' . Like where is it's structure and size of it. If you can tell me how to edit it I will customize it for myself. I cannot debug the ble module and see over the Jtag

RE: How to wire I2C for NRF 51822 with MPU 9250.What SDK should I use?

Sigurd — Tue, 26 Sep 2017 13:40:26 GMT

If you don't want all the three values to be stored together in one BLE characterstic, you would need to create a seperate characterstic for each of the x,y,z values.

RE: How to wire I2C for NRF 51822 with MPU 9250.What SDK should I use?

priya — Mon, 25 Sep 2017 16:09:27 GMT

I tried debugging in simulator mode just to see the code sequence but I couldn't step into the ble mpu update functions and many other functions.

RE: How to wire I2C for NRF 51822 with MPU 9250.What SDK should I use?

priya — Thu, 21 Sep 2017 14:36:01 GMT

I understood the Hexadecimal value. Now my code has 0x 0000 for x and 0000 for y and 0000 for z . The zeros have some hexadecimal value. Where should I modify to give X,Y Z values seperately on different lines in the app. Is that even possible. I mean I don't want all the three x,y,z values to be one huge value hexadecimal value. There are many functions like void ble_mpu_update, ble_char_accel_add. What should I modify?

RE: How to wire I2C for NRF 51822 with MPU 9250.What SDK should I use?

Sigurd — Wed, 20 Sep 2017 15:15:25 GMT

Ok, yes, the "three arrows" enables the BLE notification. It will by default be updated every 1 second. Yes, this is the Accel values. The MPU is very sensitive, and the values will change with a small amount even if the MPU is not moving.

RE: How to wire I2C for NRF 51822 with MPU 9250.What SDK should I use?

priya — Wed, 20 Sep 2017 14:24:40 GMT

There are buttons in the app after you connect to the beacon when I select unknown service. There are up/down arrow buttons for read/ write.When the button with three down arrows is selected, It reports the continuos values. These values are Heaxadecimal , what are they ? Are they Accel values?

RE: How to wire I2C for NRF 51822 with MPU 9250.What SDK should I use?

Sigurd — Wed, 20 Sep 2017 09:06:43 GMT

The accelerometervalues can be found in accel_values. There is a timer that sets the start_accel_update_flag to true every 1 second. When the flag is set to true, the accelerometer values are read using the function mpu_read_accel(). If you want to send/get the values more often, you can reduce the value of TIMER_INTERVAL_ACCEL_UPDATE.

What do you mean by "three arrows" ?

RE: How to wire I2C for NRF 51822 with MPU 9250.What SDK should I use?

priya — Tue, 19 Sep 2017 15:55:32 GMT

I could connect!! Yayy!! Thank you very much Sigurd. Is the 'value' the accerometer value? How can I get the continuos values of the accelerometer. If I press the three arrows I have the values changing all the time, even If I don't move the MPU.

RE: How to wire I2C for NRF 51822 with MPU 9250.What SDK should I use?

Sigurd — Tue, 19 Sep 2017 14:28:40 GMT

Q1: Do I have to make my beacon connectable, if so how should I do it

A1: The original nrf5-ble-mpu-simple example is connectable. Are you able to use that?

Q2: The above code works only if there is a MPU board connected to it. Works meaning I see it in the nRF connect app,still I do not see any accelerometer data in the advertisement.

A2: You are probably runing into the error-handler when the MPU is not connected. Aslo in the nrf5-ble-mpu-simple example, the accelerometer data is not put into the advertising data. The central(e.g. a phone) need to connect to the beacon to get the data using the BLE Service.

RE: How to wire I2C for NRF 51822 with MPU 9250.What SDK should I use?

priya — Tue, 19 Sep 2017 14:11:02 GMT

Hello Sigurd, Can you please help me :)

RE: How to wire I2C for NRF 51822 with MPU 9250.What SDK should I use?

priya — Fri, 15 Sep 2017 21:33:23 GMT

I have attached the file with the changes for MPU support. Do I have to make my beacon connectable, if so how should I do it. The above code works only if there is a MPU board connected to it. Works meaning I see it in the nRF connect app,still I do not see any accelerometer data in the advertisement. I tried the application on couple other beacons without the MPU and I can't find them them in nRF connect.

RE: How to wire I2C for NRF 51822 with MPU 9250.What SDK should I use?

Sigurd — Wed, 13 Sep 2017 07:45:36 GMT

Note that you have now configured the beacon kit to be a non-connectable beacon that only does advertising. The original code configured service/characteristic where the accelerometer data was added. You are also not initializing the MPU 9250, since you have commented out the mpu_setup() function call.

RE: How to wire I2C for NRF 51822 with MPU 9250.What SDK should I use?

priya — Tue, 12 Sep 2017 16:18:44 GMT

It finally works :) Yay!! Moving on, I cannot see the accelometer data in the advertisement. From what I read in the code it should advertise the MPU 9250 data as well. I have SCL connected to pin1 and SDA on Pin 0 of the beacon board.

RE: How to wire I2C for NRF 51822 with MPU 9250.What SDK should I use?

Sigurd — Tue, 12 Sep 2017 15:40:59 GMT

In the picture of your nRFgo studio, the chip is identified as nRF51822. If this is still the case, the beacon kit should be the one being flashed.

Make sure that the beacon kit have power after you turn the nRF52-DK off.

RE: How to wire I2C for NRF 51822 with MPU 9250.What SDK should I use?

priya — Tue, 12 Sep 2017 15:32:53 GMT

I mean the nRF52 development kit I am using to flash my program to the beacon. I thought my beacon was programmed but looks like the development kit is showing up as a nRf beacon. I am able to flash it but it doesn't show up in my nRF connect when the development kit it turned off. So I wonder if it is being flashed right.

RE: How to wire I2C for NRF 51822 with MPU 9250.What SDK should I use?

Sigurd — Tue, 12 Sep 2017 15:29:12 GMT

No, the beacon board is not setup to blink.

When you refer to "DK board" do you mean the nRF Beacon kit or the nRF5x-deveopment kit?

Are you now able to flash the beacon kit using your project?

If it's still not working, try to download the project you uploaded in the original question and try with that.

RE: How to wire I2C for NRF 51822 with MPU 9250.What SDK should I use?

priya — Tue, 12 Sep 2017 15:12:12 GMT

Does the beacon board blink ? My DK board shows up as NRF beacon. If you turn the DK off there is no nRF beacon

RE: How to wire I2C for NRF 51822 with MPU 9250.What SDK should I use?

Sigurd — Tue, 12 Sep 2017 14:59:56 GMT

That's strange. I have attached the .hex file Keil compiles below. Try to use the "Program Application" tab in nRFgo Studio, and flash the hex file there, and see if you can find the beacon kit using your phone(nRFConnect app) afterwards.

Attachment: beacon_kit.hex

RE: How to wire I2C for NRF 51822 with MPU 9250.What SDK should I use?

priya — Tue, 12 Sep 2017 14:51:01 GMT

I replicated the same. Didn't work :( . What else can I try ?

RE: How to wire I2C for NRF 51822 with MPU 9250.What SDK should I use?

Sigurd — Tue, 12 Sep 2017 14:46:09 GMT

SoftDevice in Region 1 is correct. I only changed the IRAM size on the project you uploaded. This is how it looks for me now:

RE: How to wire I2C for NRF 51822 with MPU 9250.What SDK should I use?

priya — Tue, 12 Sep 2017 14:40:23 GMT

My NRFgo studio has softdevice in Region1. Is that wrong? I have attached the picture of my go studio in the main question. I will try again anyway. Please let me know the starting address and size of ur ROM1 and RAM1 so that I can replicate the same.

RE: How to wire I2C for NRF 51822 with MPU 9250.What SDK should I use?

Sigurd — Tue, 12 Sep 2017 14:33:01 GMT

I tested the example in the folder: SDK_folder\examples\nrf5-mpu-examples-master\nrf5-ble-mpu-simple\pca10028\s130\arm5_no_packs\twi.

After opening the example I changed the IRAM1 size to 0x1F80, and flashed the example. I used SoftDevice S130 v2.0.1.

The beacon kit started advertising, and showed up as N/A(nRF Beacon) in nRFConnect mobile app.

RE: How to wire I2C for NRF 51822 with MPU 9250.What SDK should I use?

priya — Mon, 11 Sep 2017 19:23:43 GMT

DLL: V5.10n, compiled Feb 19 2016 18:39:11 Firmware: J-Link OB-SAM3U128-V2-NordicSemi compiled Sep 26 2016 11:30:32 Hardware: V1.00 S/N : 682936269

JLink Info: Found SWD-DP with ID 0x0BB11477
JLink Info: Found Cortex-M0 r0p0, Little endian.
JLink Info: FPUnit: 4 code (BP) slots and 0 literal slots
JLink Info: CoreSight components:
JLink Info: ROMTbl 0 @ F0000000
JLink Info: ROMTbl 0 [0]: F00FF000, CID: B105100D, PID: 000BB471 ROM Table
JLink Info: ROMTbl 1 @ E00FF000
JLink Info: ROMTbl 1 [0]: FFF0F000, CID: B105E00D, PID: 000BB008 SCS
JLink Info: ROMTbl 1 [1]: FFF02000, CID: B105E00D, PID: 000BB00A DWT
JLink Info: ROMTbl 1 [2]: FFF03000, CID: B105E00D, PID: 000BB00B FPB
JLink Info: ROMTbl 0 [1]: 00002000, CID: B105900D, PID: 000BB9A3 ??? ROMTableAddr = 0xF0000000

Target info:

Device: nRF51422_xxAC VTarget = 3.300V State of Pins: TCK: 0, TDI: 1, TDO: 1, TMS: 1, TRES: 1, TRST: 1 Hardware-Breakpoints: 4 Software-Breakpoints: 8192 Watchpoints: 2 JTAG speed: 1000 kHz

Erase Done. Programming Done. Verify OK. Application running ... Flash Load finished at 14:10:45