Android Question Bluetooth error

[red30]

I took a programm from the first post (BluetoothAdmin Tutorial) as an example but used the tablet connected with bluetooth module HC-05(which is connected to microcontroller) instead of two android devices.
The search of bluetooth devices is a very long (about 1-2 minutes) on some devices, and when it is over, I choose the device and it gives me an error - as in the picture below. Why is this happening? How to fix it?

 

[Erel]

See this example: https://www.b4x.com/android/forum/threads/hc-05-classic-bluetooth.66677/#content

 

[red30]

Yes, you are right with your program, everything is fine! But why this error is with me? What am I doing wrong?

See this example: https://www.b4x.com/android/forum/threads/hc-05-classic-bluetooth.66677/#content

The example I saw. I need to automatically search for devices has been ...

What is this error? Where to find me?

 

[Erel]

I need to automatically search for devices has been ...

It searches for a device named HC-05. See Starter service code.

One error in your code is that you are using prefix mode although it is not implemented on both sides.

 

[red30]

It searches for a device named HC-05. See Starter service code.

One error in your code is that you are using prefix mode although it is not implemented on both sides.

Can you explain a bit more?
Why on most devices operate normally?

 

[Erel]

Prefix mode can only work if both sides of the connection implement the prefix protocol (add 4 bytes with the message length).