Sending custom BLE characteristic to SD card

RE: Sending custom BLE characteristic to SD card

Jørgen Holmefjord — Mon, 17 Sep 2018 09:29:10 GMT

Can you test with an older version of Segger Embedded Studio? I doubt that this should make any difference, but SDK 15.0.0 is tested with SES v3.34. If this does not work, I'm afraid I do not have any other ideas than trying the application with different hardware. It's very hard to debug this when your code is working on my board.

RE: Sending custom BLE characteristic to SD card

RO — Fri, 14 Sep 2018 12:09:34 GMT

This tutorial is what I had followed.

STEP 6:

"Whenever a characteristic is written to, a BLE_GATTS_EVT_WRITE event will be propagated to the application and dispatched to the functions in ble_evt_dispatch(). So this means that we need to add another case to our ble_cus_on_ble_evt switch-case statement, namely BLE_GATTS_EVT_WRITE"

"we get the Write event we have to get hold of the Write event parameters that are passed with the event and we have to verify that the the handle that is written to matches the Custom Value Characteristic handle"

RE: Sending custom BLE characteristic to SD card

Jørgen Holmefjord — Fri, 14 Sep 2018 07:22:18 GMT

That line was showing because my nRF Connect was set to perform bonding on connection. This should not be necessary for writing the characteristics (I have tested without bonding, and I'm still able to see the flag getting set).

What did you use to write the characteristics?

RE: Sending custom BLE characteristic to SD card

RO — Tue, 11 Sep 2018 12:32:07 GMT

So the expected log (<info> app: Connection secured: role: 1, conn_handle: 0x0, procedure: 0) is from the peer manager event handler pm_evt_handler().

This log is missing in my RTT output whereas it appears in yours.

I have nRF2DK v1.1.1. I haven't made any modifications, just used jumper wires to connect to the SD card holder.

RE: Sending custom BLE characteristic to SD card

Jørgen Holmefjord — Tue, 11 Sep 2018 12:10:44 GMT

Did you add any log messages in peer_manager_init? There is no log messages in the code you uploaded. I also tested to add log messages to peer_manager_init, and they are printed as expected. Which version of the nRF52 DK are you using? Have you made any modifications to the board?

RE: Sending custom BLE characteristic to SD card

RO — Mon, 10 Sep 2018 23:46:42 GMT

So I disabled fatfs_init function, and I still don't see logs from peer_manager. That means the issue isn't related to the SD card?

RE: Sending custom BLE characteristic to SD card

Jørgen Holmefjord — Mon, 10 Sep 2018 13:39:33 GMT

That should be easy to test. Try to comment out anything related to fatfs/SD card and see if you get the logs immediately from peer_manager. You can disable deferred logging, but this will cause the application to spend significantly longer time processing the logs. You should limit/avoid using logs in interrupt context when logger is configured in non-deferred mode.

RE: Sending custom BLE characteristic to SD card

RO — Mon, 10 Sep 2018 13:27:06 GMT

At the moment, I do not have extra hardware.

Since the log output is missing from the peer_manager_init() function, I was guessing it might have something to do with BLE side of things rather than the SD card/socket side?

And also since I set the NRF_LOG_DEFERRED to 0, that should disable deferred mode?

RE: Sending custom BLE characteristic to SD card

Jørgen Holmefjord — Mon, 10 Sep 2018 09:22:55 GMT

In that case, I think this must be caused by HW issues, either with your board or with SD card (socket board). It's working fine on my board. If you do not get the outputs from NRF_LOG, this could indicate that the application is stuck somewhere (the logger is configured in deferred mode, meaning that the logs is not output before idle_state_handler is called at end of main - when all other code execution is complete and the IC is ready to enter sleep mode).

Do you have another board and/or SD card/socket that you can test with?

RE: Sending custom BLE characteristic to SD card

RO — Mon, 10 Sep 2018 02:36:48 GMT

UPDATE: I got the nRF LOG to appear, I had to set NRF_LOG_DEFERRED to 0 in sdk_config file.

Here is the screenshot from RTT terminal now:

As you can see, the following line is missing as compare to the output from your RTT terminal : "<info> app: Connection secured: role: 1, conn_handle: 0x0, procedure: 0" which is the log output from peer_manager_init() function.

What might be happening?

RE: Sending custom BLE characteristic to SD card

RO — Fri, 07 Sep 2018 16:00:03 GMT

I downloaded a new copy of SDK 15.0, unzipped it, copied the example I uploaded in this thread to example folder in the new SDK, ran it, and I'm getting the same result.

The program doesn't seem to enter the if(flag) condition in my case.

I can't think of ideas of what might be going wrong. Any other red flags you may think off?

RE: Sending custom BLE characteristic to SD card

Jørgen Holmefjord — Fri, 07 Sep 2018 14:28:17 GMT

Yes.

RE: Sending custom BLE characteristic to SD card

RO — Fri, 07 Sep 2018 14:14:57 GMT

I apologise, it is SDK 15.0 , I was looking at the latest download available on the website. So I should retry with SDK 15.0 right?

RE: Sending custom BLE characteristic to SD card

Jørgen Holmefjord — Fri, 07 Sep 2018 14:12:26 GMT

The project does not compile with SDK 15.1, are you sure you did not use SDK 15.0?

RE: Sending custom BLE characteristic to SD card

RO — Fri, 07 Sep 2018 14:05:22 GMT

Just to confirm, I'm working with the latest SDK v15.1
I shall download it again and try

RE: Sending custom BLE characteristic to SD card

Jørgen Holmefjord — Fri, 07 Sep 2018 13:56:22 GMT

Are you sure you have not made any other changes to the SDK? Can you please try with a fresh unzipped SDK and the example you uploaded in this thread?

RE: Sending custom BLE characteristic to SD card

RO — Fri, 07 Sep 2018 03:30:41 GMT

Just another observation, when I remove flag condition from main(and dont set flag in from on_cus_evt()), I can write to the SD card.

And even when I set the flag in services_init() it works and use flag condition in main(), it works.

It looks like setting the flag in the function for handling custom BLE events is not working as it should.

RE: Sending custom BLE characteristic to SD card

RO — Thu, 06 Sep 2018 14:53:22 GMT

For some reason I still cant get the RTT logs to appear in the debug terminal, so I added a printf statement in on_connect() to show that BLE connection has been established.

I paused execution after connecting and writing 0x01 to the characteristics.

RE: Sending custom BLE characteristic to SD card

Jørgen Holmefjord — Thu, 06 Sep 2018 14:35:44 GMT

In your image there is no output in the terminal indicating that you have connected. I meant that you should pause the execution after connecting and write 0x01 to the characteristics, to see if the application is stuck somewhere. Please also include the screenshot of the whole SES workspace, including the assembly view shown when debugging (this can give further indications on where the application is when you pause execution).

RE: Sending custom BLE characteristic to SD card

RO — Thu, 06 Sep 2018 14:18:10 GMT

When I pause, after writing the to the characteristic from the phone, the application indicates to the if(flag) statement in main.

RE: Sending custom BLE characteristic to SD card

Jørgen Holmefjord — Thu, 06 Sep 2018 14:08:29 GMT

On what line/instruction did the application stay at when you paused the execution? You cannot continue execution when the softdevice have been enabled. This will cause a hardfault, as the softdevice have not been able to handle timing critical events during the time the CPU was halted by the debugger.

RE: Sending custom BLE characteristic to SD card

RO — Thu, 06 Sep 2018 13:59:06 GMT

I am testing it on a nRF52 DK.

I ran a debug session, connected on the phone, wrote 0x01 to the characteristics, saw the printf statements, paused execution, ran it again, and then saw RTT logs, with a fatal error terminating execution.

Here is the screenshot of the debug console:

RE: Sending custom BLE characteristic to SD card

Jørgen Holmefjord — Thu, 06 Sep 2018 09:37:45 GMT

I connected the SD card socket board to the nRF51 DK, then I connected to the board from nRF Connect on the phone, write 0x01 to the characteristics. I see from the RTT output that the file is written. I remove the SD card from socket and put it in SD Card reader of computer to verify that the string is written.

Which board are you testing this on? You should try to pause the execution when debugging to see if you are stuck somewhere waiting for the SD card write, etc.

RE: Sending custom BLE characteristic to SD card

RO — Wed, 05 Sep 2018 15:43:46 GMT

So when I run the FATFS example project, it writes the SD card, with the same hardware connections. I can see "SD card example" in NORDIC.TXT. But when I switch to the custom BLE service project, I don't see the new string written to the file.

Sorry for being naive, did you actually wire up hardware to an SD card reader and open the NORDIC.TXT file in the SD card?

Also, without the UART initialization and retarget module, I see the other printf lines from main and the event handler. I just dont see printf lines from fatfs_write.

RE: Sending custom BLE characteristic to SD card

Jørgen Holmefjord — Wed, 05 Sep 2018 15:26:57 GMT

Sounds like you have not connected the SD card correctly, or there is some issue with the initialization. I checked the content of the card, and do see the string " SD card example from BLE" in file NORDIC.TXT.

RTT is working in your example, but you might not be able to use RTT Viewer when debugging. You should be able to see the RTT output in console window of SES when debugging.

I can't see any UART initialization in your application, neither have you included/enabled the module retarget.c, which retargets the STDIO functions (i.e., forwards printf data to UART). You will not be able to use printf without this.