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innoveit / react-native-ble-manager

React Native BLE communication module
http://innoveit.github.io/react-native-ble-manager/
Apache License 2.0
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requestMTU never resolves #1183

Open kurogalaxy opened 4 months ago

kurogalaxy commented 4 months ago

Describe the bug After connecting I call the requestMTU method and it never resolves so the app won't continue with the flow.

To Reproduce Steps to reproduce the behavior:

  1. Ask all permissions/Check permissions
  2. Scan devices
  3. Connect to device
  4. Call requestMTU with different sizes (128, 256, 512)

Expected behavior requestMTU should resolve with either an error or a number.

Screenshots If applicable, add screenshots to help explain your problem.

Smartphone (please complete the following information):

Additional context On my Android 13 phone it usually works but there are some times that it won't resolve either.

aidansauce commented 4 months ago

I've seen the same thing today when porting some code that was written against a much older version (7.4.1). However, when I stepped through the code in Android Studio I couldn't recreate it.

That's led me to add a 500ms sleep between the connect promise resolving and calling requestMTU which seems to be enough

I added some extra logging to try and find the issue and I'm reasonably sure that in Peripheral.java gatt.requestMtu() is being called, but onMtuChanged is not so this may be a behaviour change in Android (or maybe Samsung?) since my code was last used.

marcosinigaglia commented 1 month ago

This issue is stale because it has been open 180 days with no activity. Remove stale label or comment or this will be closed in 7 days.

thomasttvo commented 1 month ago

On Android 14 (not sure about 13) I ran into this for any value smaller than 23, but then I realized it's the standard BLE protocol that the MTU is 23 or higher, so maybe that explained it. I think react-native-ble-manager should add a line in requestMTU that ensures the value is higher or equal 23

requestMTU(peripheralId: string, mtu: number) {
   mtu = Math.max(mtu, 23);