Characteristic tutorial : error when adding a characteristic to a service

[Geoffroy]

I have a question concerning this tutorial : devzone.nordicsemi.com/.../ble-characteristics-a-beginners-tutorial

i have same problem than Milton (comment under the tutorial) : "I was able to add a custom service and verify it successfully on MCP. However, when I included the code to add a characteristic to the service, I always get "NRF_ERROR_INVALID_PARAM'."

he found a solution :

//for service
err_code = sd_ble_uuid_vs_add(&base_uuid, &m_base_uuid_type);
uuid.type   = m_base_uuid_type;
uuid.uuid   = BLE_UUID_OUR_SERVICE_UUID;

//For the characteristic:

char_uuid.uuid      = BLE_UUID_OUR_CHARACTERISTC_UUID;
char_uuid.type      = m_base_uuid_type;

i tryed his solution but i failed, i think it's because i do'nt know how to implement correctly the solution ...

(the tutorial work and advertise for me until this problem)

[awneil]

Geoffroy said:

I always get "NRF_ERROR_INVALID_PARAM'."

Where, exactly, do you get that?

Have you tried stepping into whatever is giving that result to see precisely what triggers it?

[Geoffroy]

In file from solution (https://github.com/NordicPlayground/nrf5-ble-tutorial-characteristic/blob/master/Solution/our_service.c), in our_service.c line 85 where function sd_ble_gatts_characteristic_add is called the return give NRF_ERROR_INVALID_PARAM :

    // OUR_JOB: Step 2.E, Add our new characteristic to the service
		err_code = sd_ble_gatts_characteristic_add(p_our_service->service_handle,
                                   &char_md,
                                   &attr_char_value,
                                   &p_our_service->char_handles);
		APP_ERROR_CHECK(err_code);

then program fails on APP_ERROR_CHECK. if i comment (just to try) this check, i can see advertising and service, but service is empty (quite logical because it failed)

i tryed to stepp in but it's quite difficult to understand with macros...

I also wonder if it could be due to bad values for defines (like in config_sdk.h)...

[awneil]

OK - the sd_... calls are all SVC "calls" into the SoftDevice - so you can't step into them.

So use the debugger to look at all the parameters you are passing - do they all look OK?

The comment describing sd_ble_gatts_characteristic_add() says this about when it will return NRF_ERROR_INVALID_PARAM:

 * @retval ::NRF_ERROR_INVALID_PARAM Invalid parameter(s) supplied, service handle, Vendor Specific UUIDs, lengths, and permissions need to adhere to the constraints.

Geoffroy said:

wonder if it could be due to bad values for defines (like in config_sdk.h).

Did you Try increasing NRF_SDH_BLE_VS_UUID_COUNT to 4 - as Marjeris Romero said?

[Geoffroy]

yes i try ed to increase NRF_SDH_BLE_VS_UUID_COUNT to 4

without success, same error

[awneil]

Which question was that a "yes" to?

EDIT

So what about the other question, then?

awneil said:

use the debugger to look at all the parameters you are passing - do they all look OK

[Geoffroy]

for p_our_service->service_handle i get 0x000B

i don't know yet where does it come from, maybe :

#define BLE_L2CAP_CH_STATUS_CODE_UNACCEPTABLE_PARAMS    (0x000B)  /**< Unacceptable parameters. */

edit p_our_service->service_handle is modified in our_service_init in fucntion sd_ble_gatts_service_add but i can't go further becase it's macro...