Adding NUS to existing profile - how to get a 'link context' ?

[eyalasko]

Hi, 

I'm trying to add the NUS service to an existing application (freertos based, SDK15.2, already use a custom service)

• I copied the relevant code snippets from the example
• Modified the project setup - Add ble_nus.c & ble_link_ctx_manager.c, increased start address + 0x10 bytes (for the additional service uuid)
• Updated sdk_config.h - increased NRF_SDH_BLE_VS_UUID_COUNT to 2 (was 1 for the prev proprietary service), BLE_NUS_ENABLED = 1

The app builds and runs to the point where I do BLE connect.

The program crash when ble_nus.c on_connect() function calls blcm_link_ctx_get(), as the 1st parameters p_nus->p_link_ctx_storage == NULL.

I had to add ble_link_ctx_manager.c to the project following the example project. However, I couldn't find what it does and how it is used/initialized

Any advice will be appreciated.

Thanks

[Amanda Hsieh]

Hi,

Please check sdk_config.h. NRF_SDH_BLE_VS_UUID_COUNT parameter should  be greater than zero

Softdevice should be configured to accept Vendor Specific UUIDs, like NUS Nordic UART Service.

-Amanda H.

[eyalasko]

Hi, 

NRF_SDH_BLE_VS_UUID_COUNT is set to 2 (see OP) as I have a proprietary service + NUS.

Any insight about the 'packing' issue described above?

Thanks

[Amanda Hsieh]

Hi, 

After adding NUS to the project, you would need to allocate more RAM to the SoftDevice.

Which version of SDK do you use?

Could you provide the J-Link RTT log?

-Amanda H.

[eyalasko]

Amanda Hsieh said:

you would need to allocate more RAM to the SoftDevice.

I did. Otherwise one if the sd calls would have asserted (probably sd_ble_uuid_vs_add())

Amanda Hsieh said:

Which version of SDK do you use?

SDK 15.2, nRF52832, a project that is based on ble_app_hrs_freertos example

Amanda Hsieh said:

Could you provide the J-Link RTT log?

Attached RTT Client prints (after turning on BLE_NUS_CONFIG_LOG_ENABLED in sdk_config.h)

###RTT Client: ************************************************************
###RTT Client: *               SEGGER Microcontroller GmbH                *
###RTT Client: *   Solutions for real time microcontroller applications   *
###RTT Client: ************************************************************
###RTT Client: *                                                          *
###RTT Client: *       (c) 2012 - 2016  SEGGER Microcontroller GmbH       *
###RTT Client: *                                                          *
###RTT Client: *     www.segger.com     Support: [email protected]       *
###RTT Client: *                                                          *
###RTT Client: ************************************************************
###RTT Client: *                                                          *
###RTT Client: * SEGGER J-Link RTT Client   Compiled Aug 30 2018 17:38:24 *
###RTT Client: *                                                          *
###RTT Client: ************************************************************

###RTT Client: -----------------------------------------------
###RTT Client: Connecting to J-Link RTT Server via localhost:19021 .... Connected.
SEGGER J-Link V6.46 - Real time terminal output
J-Link OB-SAM3U128-V2-NordicSemi compiled Jan  7 2019 14:07:15 V1.0, SN=682324592
Process: UV4.exe
<info> app: *** myApp started [Jul  9 2019 22:52:34] ***
<info> app: <<<===  myApp 0.20.28.CF771A (Jul  9 2019 22:52:34) starting... ===>>>
<info> app: *** myApp started [Jul  9 2019 22:52:34] ***
<info> app: <<<===  myApp 0.20.28.CF771A (Jul  9 2019 22:52:34) starting... ===>>>
<info> app: Fast advertising.
<warning> app:  !! Pulse fault: status code = 0x40
<warning> app:     Pulse fault cleared
<error> hardfault: HARD FAULT at 0x0002E286                //  << This line triggered on connection
<error> hardfault:   R0:  0x00000000  R1:  0x00000000  R2:  0x200067F0  R3:  0x00000000
<error> hardfault:   R12: 0x000001F3  LR:  0x0003886F  PSR: 0x61000000
<error> hardfault: Cause: Data bus error (PC value stacked for the exception return points to the instruction that caused the fault).
<error> hardfault: Bus Fault Address: 0x00200028

[Sigurd]

I have not been able to reproduce this. Could you try to increase(maybe double) the below values in your FreeRTOSConfig.h file to see if that helps?

#define configMINIMAL_STACK_SIZE
#define configTOTAL_HEAP_SIZE

If that does not help, could you upload a project that reproduces the issue ?

[eyalasko]

Reviving this post...

I've tried to increase freeRTOS macros. Still the same phenomena.

I'm not sure if its relevant, but I have 2 custom services unlike the demo NUS project which has only 1.

Attaching a memory dump screenshot - a picture worth 1000 words...

Thanks

[eyalasko]

So, to wrap up the story - 

Eventually, it was a packing problem indeed but on my side.

There was one occurrence of #pragma pack(push) without matching #pragma pack(pop)... 

I hope this can help any fellow developer banging his head as I  did.

Happy new year everybody.