getting ble_app_uart_c central device connecting with peripheral

RE: getting ble_app_uart_c central device connecting with peripheral

kont40 — Fri, 23 Feb 2018 18:31:17 GMT

Hello tesc

Thanks for the advice, following it I found that the target UUID checked into is_uuid_present() was different from extracted UUID. Problem solved!!!

RE: getting ble_app_uart_c central device connecting with peripheral

tesc — Fri, 23 Feb 2018 15:56:11 GMT

Then you must look at how the central finds the peripheral. For instance, the central may filter what peripheral to connect to based on advertised name, or advertised service UUID.

An easy way to get some clues could be to let the old device advertise, and look at that advertisement data from nRF Connect.

Edit: Since you made the central device, you probably know what the central is looking for in order to connect?

RE: getting ble_app_uart_c central device connecting with peripheral

kont40 — Fri, 23 Feb 2018 14:37:41 GMT

Dear Terje,

Thanks for detailed response. As to above points:

- the device do not seem to reset;

- since I am able to see it in nRF connect on a tablet with Android OS, I believe advertising is fine.

- I am able to connect to device using nRF connect, see the characteristic and get the data from notifications.

- as to the last point - to avoid potential problems with 16-bit UUID I set back the Nordic UART service as shown in the screenshot. Also, I have changed the respective ids at the central side too, as shown in the code below. However, still can't get the two boards connect. Will appreciate any further advice.

The configuration at the central device:

#define NUS_BASE_UUID 					{{0x9E, 0xCA, 0xDC, 0x24, 0x0E, 0xE5, 0xA9, 0xE0, 0x93, 0xF3, 0xA3, 0xB5, 0x00, 0x00, 0x40, 0x6E}} /**< Used vendor specific UUID. */
#define BLE_UUID_NUS_SERVICE            0x0001                     
#define BLE_UUID_NUS_TX_CHARACTERISTIC  0x0002                      
#define BLE_UUID_NUS_RX_CHARACTERISTIC  0x0003

The peripheral seen in nRF Connect:

RE: getting ble_app_uart_c central device connecting with peripheral

tesc — Fri, 23 Feb 2018 12:09:10 GMT

Hi,

Can you confirm that it does not assert / reset? See this thread for how to debug.
Can you confirm that the device advertises?
Are you able to connect to it using nRF Connect? (Either for Android, iOS, or for desktop.)
When you change an example from using 16 bit UUIDs (as defined from Bluetooth SIG) to using custom UUIDs ("vendor specific UUIDs"), you must configure the SoftDevice to allocate space in memory for your custom UUIDs. See this thread. Please also note that in the latest SDKs the number of custom UUIDs is defined using NRF_SDH_BLE_VS_UUID_COUNT in sdk_config.h.

Regards,
Terje