RE: Difference in adding characteristics from example codes

ovrebekk — Wed, 07 Oct 2020 11:42:07 GMT

Excellent news Alexander, good to hear you were able to get it running 🙂

I will consider the case closed then.

RE: Difference in adding characteristics from example codes

AHass — Wed, 07 Oct 2020 05:24:19 GMT

Hi Torbjørn,

I successfully implemented my own GATT profile based on the Nordic UART service as you suggested. It was fast and easy.

Thank you for your great support!

RE: Difference in adding characteristics from example codes

ovrebekk — Fri, 02 Oct 2020 13:36:13 GMT

In general I would recommend using either the Nordic UART service (NUS) or the Led Button service (LBS) from SDK v17.0.2 as a starting point if you want to make your own proprietary service(s).

Both of these services are quite similar in that they set up one characteristic for sending data from the client to the server (write), and one characteristic for sending data from the server to the client (notify). The only difference is that LBS is set up to send a single byte back and forth, while NUS is set up to send strings of varying lengths, making it more suitable if you want to send a large amount of data.

To modify one of these services to your own requirements you can simply copy and rename the existing files, replace the UUID with one of your own, and change the implementation as needed to add or remove characteristics or change the characteristic properties.

As for the differences between the examples, the various service SDK implementations vary a bit in how they configure and set up the characteristics, but in the end it all boils down to a series of calls to the sd_ble_gatts_service_add(..) and sd_ble_gatts_characteristic_add(..) functions.

Best regards
Torbjørn