Trying to connect Bluetooth BP cuff, but struggling with the "characteristic UUID" stuff

I’m very new to BLE stuff, and Thunkable, so please excuse my ignorance.


I’m trying to connect and collect data from a BLE blood pressure cuff, but I don’t have a clue what I’m doing.

I’ve got some documentation from the device manufactureres about the BLE structure and all that…

  • my biggest problem is trying to figure out the “characteristic UUID”

The documentation says something like “fff4”

image

  • but when I try and receive that, I get an error saying that the system can’t read that characteristic.
    • When I look for help online, I find LONG strings for the uuid - not 4 character strings.

What am I missing?

  • I’ve gotten as far as:
    • Scanning for a list of devices
    • Selecting and connecting to a device

It’s the UUID thing that’s tripping me up, I’m sure of it.

Anyone got any advice?

  • Thanks so much!
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Use this as your UUID
0000FFF4-0000-1000-8000-00805F9B34FB

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Thank you so much for your help!!

May I ask how you got all the extra characters?

  • Are they industry standard or something???
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This is the default or base UUID for all characteristic IDs if not set by the factory.

The default is 00000000-0000-1000-8000-00805F9B34FB
If the manufacturer is giving you only 4 digit then it is assumed that you need to use the default UUID. It starts with 8 hexadecimal digits and you need to add your 4 digit hexadecimal number as the second part of it. So instead of all zeros it would be 0000 plus your code FFF4

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Thank you! @muneer

Cheers

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