Bluetooth wrongly identifies a gadget as a known device, blocks further communications

jim_m_58 said:

But is it that the WOO is advertising incorrectly?  Sounds to me that the WOO might be using the incorrect UUID.

That is actually a possibility, I'll try to check. Thanks!

I checked Vectronix and WOO UUIDs - they don't look similar in any way. Moreover, the issue is happening randomly and can't be reproduced. If you go to Sensors and click Add New, it doesn't find anything, even with several WOO turned on. Instead, a window might appear at a completely random time, saying "Vectronix sensor is found, do you want to connect?". So, it sounds like a bug more and more.

Brandon, would you be able to check with firmware team how they identify Vectronix and why it only happens randomly? Thank you!

Are you scanning and only using the WOO UUID in your app?

It uses this BLE profile:

const WOO_SERVICE = Ble.stringToUuid("00000001-0000-0000-0000-000000000080");
const WRITE_CHARACTERISTIC = Ble.stringToUuid("00000002-0000-0000-0000-000000000080");
const READ_CHARACTERISTIC = Ble.stringToUuid("00000003-0000-0000-0000-000000000080");
const BLE_PROFILE = {
:uuid => WOO_SERVICE, // Service
:characteristics => [
{:uuid => WRITE_CHARACTERISTIC,:descriptors => [Ble.cccdUuid() ] },
{:uuid => READ_CHARACTERISTIC,:descriptors => [Ble.cccdUuid() ] }]
};

I've contacted a couple of different teams and will follow up with you on this. I agree it sounds like a firmware issue, but I'm not sure how exactly to go about investigating this just yet.

Would you be willing to perhaps provide us with a WOO sensor if necessary? In cases like this, we often need to find a way to reproduce the problem before we can determine the cause. I understand it appears to be random, but if you have any other insight into how this might be reproduced, that would be appreciated.

I suppose I should also ask a rather obvious question: do you have a Vectronix device/sensor lurking anywhere that might be getting detected?

Thank you Brandon. I think sending you a WOO sensor will not be a problem. Reproducing the issue will be very hard though - it happens once in blue moon.

I don't even know what Vectronix, so it is not around. I don't think it is the cause for the problem though - the watch saves WOO's into sensors, not Vectronix.

Please let me know if you need more information. Thanks!

The issue here is likely related to the way that we “detect” that a sensor supports the Vectronix profile. (By the way, Vectronix is a generic term for a class of laser range finders that can be used in some applications: https://www.safran-vectronix.com/products/.) Currently the profile is determining that a sensor supports Vectronix by checking if it has an advertised local name, which results in basically any sensor being detected as a Vectronix device and then pairing is forced by the proximity pairing feature.

There’s ongoing discussion about how to address this, but I suspect it will ultimately require a firmware update to fix.

Thank you Brandon. We are looking forward to more news on this issue.

Those UUIDs look very odd to me.  Where are you getting them from?

They look too generic to me.  The 0001, 0002, 0003 part is common for ID'ing UUIDs for services and characteristics on a device, but the fact that everything else is zero except one bit I've never seen.