IOS Bluetooth Connection

[espruino-discuss2]

Posted at 2022-02-08 by user137198

It used to be that I could only make a Bluetooth connection between my iPhone and Bangle.js 2 by using WebBLE first. If I tried to connect via WebBLE, my iPhone would ask me if I wanted to allow the Bangle to receive notifications, etc. Everything would work fine, except that if I wanted to use WebBLE again after disconnecting, I would need to tell my iPhone to forget the Bangle in Bluetooth settings, and then start over. Not ideal, but it worked.

Today I upgraded my Bangle firmware to 12. Now I can ONLY connect via WebBLE. While I am connected via WebBLE, I can’t get IOS notifications (one connection at a time, I know). But when I disconnect WebBLE, IOS no longer stays connected, and I can’t see how to initiate a new connection with IOS, so notifications work, etc.

Any suggestions for how to pair IOS when I am not using WebBLE?

Thanks,
Dave

[espruino-discuss2]

Posted at 2022-02-09 by @gfwilliams

Maybe uninstall and reinstall the 'iOS' app on the Bangle? It's the iOS app that enables everything needed to to make the iPhone want to keep a connection open to Bangle.js, so it's possible that somewhere along the upgrade process that got disabled somehow?

---

Posted at 2022-02-09 by user137198

The uninstall and reinstall of just the iOS app didn’t work. But uninstalling everything, and reinstalling, did work. Thanks for your help.

[eisengpferd]

Hi, I just searched for my problem and this thread exactly fits for me:

I have two bangle.js2. My first one is working fine, but a bit slow, so I am testing how I can speed it up. Other Firmware, uninstalling some apps...

Now with my second bangle I tested the firmware 2.28 noflash and had to reset this with DFU.

After this I have the same problem as Dave in 2022: With the iphone connect with WebBLE the iphone does not ask me for connection and to allow the messages. So after disconnect from WebBLE there are no messages coming through to the Bangle.
Second strange behavior: After connecting with windows11 I can not make a new connection. Error: Device connection failed, Invalid JSON
Only a windows restart makes it possible to reconnect with the bangle.

reinstalled Firmware regular 2.28
Factory reset with the bangle utility
only installed "ios connection" v0.24
nothing else changed.

Another observation: After Windows restart and successfully connect to the bangle it shows the message: "hold BTN3 to reload"
I have never seen the BTN3 message in a Bangle.js2 before... Something must be different here...

Any idea? How can I "really" reset the bangle to factory settings?

[gfwilliams]

I think this is probably related to the fact that as part of trying noflash (https://github.com/orgs/espruino/discussions/7747) I think you flashed a very old build onto your Bangle? and that could have messed up pairing info that was stored.

Try long-pressing the button to reboot right through into the recovery menu. I believe when you do this all pairing info on the Bangle (which could now be corrupt) is cleared out - then you need to make sure you 'forget' the Bangle on iOS/Windows are try connecting/pairing again and maybe that'll help.

If you do a factory reset from the recovery menu that'll ensure all the app data is wiped and replaced with the correct Bangle.js 2 code as well as it's stored in Bangle's flash - but you'd have to reinstall iOS integration manually.

Talking of that - did you 'hold the button to reload' before trying to pair with your iOS device? If you don't do that then it won't load the code that makes iOS want to pair with it.

Finally, after you have installed iOS integration and long-pressed, make sure you turn Bluetooth off on your iPhone and back on. iOS caches Bluetooth characteristics, so it would 'rememeber' what the Bangle had on it before and not even bother to look for the new iOS services when trying to reconnect.

Only a windows restart makes it possible to reconnect with the bangle.

Honestly, if it works after a restart this is almost certainly a Windows/driver issue that's unrelated to Bangle.js I'm afraid. Obviously from Bangle.js's point of view absolutely nothing has changed on the device when you restart your PC.

After Windows restart and successfully connect to the bangle it shows the message: "hold BTN3 to reload"

Could you have chosen 'Bangle.js 1' as the device in the top left of the App Loader for some reason? Usually it should be auto-populated, but if that got changed and it's forcing it to download Bangle.js 1 code onto Bangle.js 2 then that could be a big soure of issues!

[eisengpferd]

thanks Gordon for your long answer.
I think I tried all these options. Reset with 2s press, long press, or recovery menu reboot.
I did a factory reset over the menu (settings, utility, factory reset) and over the recovery menu.
Switching the BT on and off several times in pc, watch, and iphone.

When I reboot (long press) and connect then with the iphone the bangle showes "hold BTN3 to reload"
I did another firmware flash to the 2v28.102 (ensured that Bangle.js 2 is selected in the app loader), but no change.

So as you said it seems to be that some old code is resident at the bangle...

How can I reset all old code? My firmware reset over web-ide did not do the trick...

[gfwilliams]

You could try calling NRF.eraseBonds() via the IDE - this should force an erase (it should be what booting while long pressing does but maybe there is some difference). You can't call it directly since you have to be disconnected for it to work, so:

NRF.sleep();setTimeout(() => NRF.eraseBonds(),1000);setTimeout(() => E.reboot(),2000)

should work - the watch will reset after a few seconds. If that doesn't work we could try manually erasing those pages of flash memory I guess.

[eisengpferd]

Honestly, if it works after a restart this is almost certainly a Windows/driver issue that's unrelated to Bangle.js I'm afraid. Obviously from Bangle.js's point of view absolutely nothing has changed on the device when you restart your PC.

but with my other bangle the behavior is completely different.
When I connect to my first bangle with Edge and the App loader my windows asks me to pair the bangle to bluetooth. And there is no problem to reconnect.
Only my second bangle has these problems...

I deleted and reinstalled my wlan/bt card of the pc. No change...
But I tried to connect with chrome (not edge) and here after close / reopen chrome I am able to connect to bangle no.2 again. But still no pairing question from windows...

[RKBoss6]

For me, a full factory reset solved my issues, and I manually reinstalled every app, so corrupted software from a backup won't get reintroduced

Edit: to do so, press and hold the button, even after a full reboot. It will open up a recovery menu. From there, do a factory reset.

[eisengpferd]

How can I do a "full" factory reset? I tried this:

• flash firmware with webIDE in dfu mode (2v28 banglejs2)
• factory reset over recovery menu
• compact storage over recovery menu

Installing IOS from https://rkboss6.github.io/BangleApps/

same problems...

[gfwilliams]

Please can you try connecting with the IDE and running:

require("Flash").erasePage(245*4096)
require("Flash").erasePage(246*4096)
require("Flash").erasePage(247*4096)

I believe this will completely wipe all the saved pairing data from the watch. After the steps you performed above I believe the code on the two devices should be identical. The long-press I suggessted should have done this already but this is the sledgehammer approach!

If you still have problems, could you try with a friend's iPhone (or an old one) and see if it behaves differently? It's possible that your iPhone still has something stored somewhere that is causing issues

[eisengpferd]

yippie you did it :-)

After these commands I reinstalled ios-connection and message. And the connection with pc or iphone now triggers the pairing message.

Perhaps these commands could be triggered each time when ios-connection is installed / or deinstalled.
But why all the "factory resets" did not erase these fields?

Thanks /Hendrik/

[gfwilliams]

The factory reset just resets the JavaScript code, and it was expected that long-pressing the button at reboot cleared out pairing info anyway. All I can assume is the memory area there got corrupted in such a way that Nordic's built-in libs got confused and didn't clear it properly.

I've just changed it to when 2v29 is released, a factory reset will clear out any data from those memory areas