B4J Question reading data from a module Bluetooth

[f0raster0]

Hi guys - Sorry if asking too much, just trying to use B4J

I'm looking for some way to communicate a B4J App with my module nRF52 - like this examples but now using B4J

Maybe the question could be:
Have anyone tried to connect to a Bluetooth module? Using the computer's Bluetooth or the only option will be using an external Bluetooth?

Some thing similar to this, I want to connect to the module and read data - for now

jBluetooth library

This library allows you to discover and connect to Bluetooth devices. It is similar to B4A Serial library. It is based on the BlueCove open project (Apache license): http://bluecove.org/ This library runs on Windows. A modified version for Raspberry Pi is available here...

www.b4x.com

Edit: At this stage, looking for the best alternative to communicate a B4J App to my modules then open to options.

 

[Erel]

Don't confuse classic Bluetooth with BLE. These are two completely different things.

AFAIK, there is no BLE library available for B4J.

 

[f0raster0]

no, no..

I'm lost about B4J, the JBluetooth (I think) can be used to find modules Bluetooth (for example a printer, etc)
but the example is showing: "Bluetooth not available",

 

[Erel]

jBluetooth only works with specific Bluetooth drivers.
jSerial with a mapped virtual serial port will work better when it is suitable.

 

[GabrielM]

There can be other methods, I can only tell about my experience using BLE on a windows machine.
That B4J project needed to receive BLE advertising from a specific device sending its Beacon data.

As could not find a BLE library for B4J I though to consider writing a small Netcore 3.1 C# app (excerpt attached) , that will start a BLE Advertisement Watcher, get the data I was after and send it via a HTTP port on the local machine so the B4J app will get that stream via a server socket and further process it.
While the BLE device was sending advertisements at a 300ms period the best period I got them was about 3.2 seconds, and also not at a constant rate. Tested with external BLE.4 and BLE.5 USB Dongles attached to the machine.
The solution eventually dropped due to this inconsistency.

Spoiler: B4J serversocket related code

Public BLEbuffer() As Byte ' gets updated on receiving data stream on socket
Private server As ServerSocket

' initialize in AppStart
server.Initialize(51042, "server")
server.Listen


Sub server_NewConnection (Successful As Boolean, NewSocket As Socket)
If Successful Then
astream.Initialize(NewSocket.InputStream, NewSocket.OutputStream, "astream")
End If
server.Listen
End Sub

Sub astream_NewData (Buffer() As Byte)
BLEbuffer = Buffer ' update BLE receive buffer
count_adverts = count_adverts + 1
Log($"Adv.Received: ${count_adverts} @ $Time{DateTime.Now} , ${BytesToString(Buffer, 0, Buffer.Length, "utf8")} "$)
isReceiving = True ' just got data from streamer
End Sub

' Example: need to kill the server if exit the app, etc
Public Sub Kill_Server
server.Close
ProcessKill("your_beacon_rx.exe") ' the name of the C# produced executable
End Sub

Finally, ended up making own USB Dongle based on NRF52840, that will listen for Beacon advertisements and relay them on a virtual serial port that was used by the B4J app, receiving periods were matching exactly the fast pace advertising periods from the external Beacon device.