central discovery error

[bloobird0]

Hello,

I am currently working on a project involving the nRF52DK to be a central device.

The peripheral device is based on the Nordic Uart service with minor changes: UUID, access properties...

On the central side, I use ble_nus_c as an example but get an error which I can solve currently.

I am able to connect but not able to finish a GATT database discovery. The NUS service is found but not the characteristics. In ble_db_discovery.c, sd_ble_gattc_characteristics_discover return value 0x11. I guess that the input parameters are wrong but why, the handles are calculated by this module when the service is discovered?

I use the ble_nus_c service module only with a modified base UUID up to now.

Anyone could help? If so, what kind of information would you need? What should I look at with the debugger?

Thanks in advance for your help.

[Petter Myhre]

0x11 is NRF_ERROR_BUSY - Client procedure already in progress What modifications have you made to the ble_app_uart_c example? Do you have a sniffer trace? Maybe you can upload your complete projects so I can test them here?

[bloobird0]

Hello,

according to the trace in RTT Viewer, I can see that an ATT MTU update is being processed during the discovery, could it be a process that make the system busy?

[Petter Myhre]

Yes, it could.

[bvt]

I'm having this same issue, and I don't believe the MTU update is the answer.

[Petter Myhre]

@bvt I think you should add a new question, and link to this one if it is relevant. Please try to include what modifications you have made to the ble_app_uart_c example, or even the complete project. A sniffer trace could also be very helpful.