How to change my NUS_BASE_UUID

[role_2099]

I want to modify the uuid through the serial port. What variables can I use to describe this define? Is there any code for reference?

#define BLE_UUID_NUS_TX_CHARACTERISTIC 0x0003               /**< The UUID of the TX Characteristic. */
#define BLE_UUID_NUS_RX_CHARACTERISTIC 0x0002               /**< The UUID of the RX Characteristic. */
#define NUS_BASE_UUID                  {{0x9E, 0xCA, 0xDC, 0x24, 0x0E, 0xE5, 0xA9, 0xE0, 0x93, 0xF3, 0x27, 0x05, 0x00, 0x00, 0x40, 0x6E}} /**< Used vendor specific UUID. */

Best wishes and regards!

John

[awneil]

Why do you want to change it?

I'm not sure that the nRF5 SDK supports dynamically changing services at runtime?

This tutorial series explains about custom Characteristics and Services in the nRF5 SDK:

https://devzone.nordicsemi.com/nordic/short-range-guides/b/bluetooth-low-energy/posts/ble-services-a-beginners-tutorial

https://devzone.nordicsemi.com/nordic/short-range-guides/b/bluetooth-low-energy/posts/ble-characteristics-a-beginners-tutorial

role_2099 said:

What variables can I use to describe this define?

just find where they are used in the code - and change that to use something else.

But, again, I'm not sure that the nRF5 SDK supports dynamically changing services at runtime?

[role_2099]

Hi awneil,

Thank you for your reply. Let me take a look at the two links you sent. I just tried to modify BLE_UUID_NUS_SERVICE, but they all failed. It prompted him to be a constant and cannot be changed to a variable.

[awneil]

Still leaves the question of why you want to do this?

www.catb.org/.../smart-questions.html

[ovrebekk]

Hi John

If you look at the top of the ble_nus_init(..) function, on line 252 of ble_nus.c, you can see where the nus_base_uuid variable is created using the NUS_BASE_UUID define to set its value. 

It is definitely possible to change the ble_nus_init function to take the UUID as a parameter instead, so that you can change this at runtime. 

Please note that you can not change a service already in the SoftDevice, so if you have configured the SoftDevice already you need to disable it, enable it again, and configure the services again with the new UUID. 

Also, I don't recommend changing the SDK files directly. If you want to make changes to the ble_nus.c implementation I recommend making a local copy of the file in your project folder, and rename the file and the functions to make it clear that you are not using the standard Nordic UART service anymore, but your own proprietary service.

Best regards
Torbjørn