how to built a 128 UUID bit

RE: how to built a 128 UUID bit

endnode — Fri, 19 May 2017 08:18:03 GMT

Add 128-bit base UUID to SoftDevice ATT/GATT table? Yes and no. If you don't care to receive 2-byte UUID + BLE_UUID_TYPE_UNKNOWN type for 128-bit base then you can go with it. Otherwise you need to provision all 128-bit bases to the stack because that's how Soft Device work on GATT layer, whatever Client or Server role.

RE: how to built a 128 UUID bit

bjorn-spockeli — Fri, 19 May 2017 08:17:28 GMT

Oh, my bad. Yes, then you need to take a look at the ble_app_uart_c example, specifically the ble_nus_c_init function, where you add the vendor specific UUID.

RE: how to built a 128 UUID bit

DavidC — Fri, 19 May 2017 08:12:42 GMT

I'm doing an app for central and I need to discover a service which has a 128 uuid, Do I need to add it?

RE: how to built a 128 UUID bit

endnode — Fri, 19 May 2017 07:59:27 GMT

Well the examples/ble_central/ble_app_uart_c is counterpart of examples/ble_peripheral/ble_app_uart, isn't it?

RE: how to built a 128 UUID bit

bjorn-spockeli — Fri, 19 May 2017 07:57:05 GMT

No, ble_app_uart found in examples/peripheral/ble_app_uart.

RE: how to built a 128 UUID bit

DavidC — Fri, 19 May 2017 07:49:11 GMT

is the NUS example the BLE_APP_UART_C?

RE: how to built a 128 UUID bit

endnode — Thu, 18 May 2017 13:40:41 GMT

As Turbo J explained, Nordic Soft Device runs (in the spirit of BT SIG) on 16-bit short UUIDs and 128-bit base UIDs during any GATT operation. So you will get structure of short 2-byte UUID value and reference to internal "table" of 16-byte UUID bases. By default Soft Device knows only BT SIG one and all the rest is treated as "unknown". If you know at start up which proprietary UUIDs you will use then you can provision them to the Soft Device (but you will need to remember which index is which). If not then you can either do it later during run-time or simply do this outside of Soft Device by reading full 128-bit UUID value by proper GATT commands (this is applicable for GATT Client only of course).

RE: how to built a 128 UUID bit

Turbo J — Thu, 18 May 2017 13:18:48 GMT

You cannot use a 128-bit UUID directly with sd_ble_gattc_primary_services_discover(). These 128 bit UUIDs must first be added to the softdevice via sd_ble_uuid_vs_add() call.

The NUS (Nordic UART) example uses this to implement the custom UUID Uart service, so look at its source code on how to use these functions properly.

RE: how to built a 128 UUID bit

DavidC — Thu, 18 May 2017 12:43:48 GMT

My sensor has BLE, that's not the problem. it is using a cypress chip and I'm pretty sure that uses BLE

RE: how to built a 128 UUID bit

Turbo J — Thu, 18 May 2017 12:35:28 GMT

This UUID is reseved for bluetooth classic SPP. Your sensor probably does not support Bluetooth low energy at all.