why UUID reversed after registered

[piepie]

Hi guys,

I notice that the bytes array of UUID is reversed after registerd.

For example, I define the UUID marco as follows and registe it at ble_nus_init(). #define NUS_BASE_UUID {{0x9E, 0xCA, 0xDC, 0x24, 0x0E, 0xE5, 0xA9, 0xE0, 0x93, 0xF3, 0xA3, 0xB5, 0x00, 0x00, 0x40, 0x6E}} /**< Used vendor specific UUID. */

Anyway, I find this service UUID appears on the nRF Connecter is: 6E400000B5A3F393E0A9E50E24DCCA9E

Quite confused. Which order is fit for the UUID rule? Why it is reversed after registerd in softdevice?

[RK]

Because it's transmitted little-endian per the spec. So if you define it like that as a sequence of bytes then the first one will be the last one.

[piepie]

Now I got it.The bytes displayed in the MCP is big-endian. thanks, RK.