How to define 128 bit UUID in arduino

Question

I have a question for how to define BLE 128 bit service UUID in arduino.

I can see 16 bit UUID in example like this:

define SERVICE_UUID_BATTERY (0x180F)

but how to define the 128 bit UUID in arduino?

Thanks

score 3 · Accepted Answer · answered Dec 09 '15 at 22:54

3

It can be defined this way:

/* 00000000-ABCD-FEED-F00D-012345678900 decided as custom ID. */
uint8_t UUID[] = { 0x00, 0x89, 0x67, 0x45, 0x23, 0x01, 0x0D,0xF0, 0xED, 0xFE,     0xCD, 0xAB, 0x00, 0x00, 0x00, 0x00 };

answered Dec 09 '15 at 22:54

Blurmylife

71
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score 0 · Answer 2 · edited May 23 '17 at 12:14

0

As Arduino is based on C++, I don't think this is possible because :

GCC does have an uint128_t/int128_t type, starting from version 4.something (not sure here). I do seem to recall, however, that there was a __int128_t def before that.

Source

But you can try to have a look at this thread : Representing 128-bit numbers in C++

Maybe you can use this librairie in Arduino...

edited May 23 '17 at 12:14

Community

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answered Dec 02 '15 at 16:44

Raphaël Vigée

2,048
14
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Thanks Raphael, let me try the library. – Blurmylife Dec 02 '15 at 17:17
hi Raphael, i think i found the answer, thanks for the help. – Blurmylife Dec 09 '15 at 22:55
GCC only defines 128-bit integer types on 64-bit targets (where it takes 2 registers). Arduino is AVR, where __int128 would take 16 registers. Or 32-bit ARM, but not AArch64. – Peter Cordes Feb 21 '19 at 20:19

How to define 128 bit UUID in arduino

define SERVICE_UUID_BATTERY (0x180F)

2 Answers2