B4A Library felUsbSerial - Alternative Usb Serial library

This library wraps the following open source project: https://github.com/felHR85/UsbSerial (MIT license).

It is an alternative to the UsbSerial2 library.

The following devices are supported: CP210x, CDC, FTDI, PL2303 and CH34x.

Usage is simple. You find the UsbDevice with USB library and then initialize felUsbSerial, configure it and start reading.

Sub Process_Globals
   Private usbserial As felUsbSerial
   Private manager As UsbManager
   Private bc As ByteConverter
End Sub

Sub Globals

End Sub

Sub Activity_Create(FirstTime As Boolean)
   If FirstTime Then
     manager.Initialize
   End If
   Dim btnConnect As Button
   btnConnect.Initialize("btnConnect")
   btnConnect.Text = "Connect"
   Activity.AddView(btnConnect, 10dip, 10dip, 100dip, 100dip)
End Sub

Sub btnConnect_Click
   If manager.GetDevices.Length = 0 Then
     Log("No connected usb devices.")
   Else
     Dim device As UsbDevice = manager.GetDevices(0) 'assuming that there is exactly one device
     If manager.HasPermission(device) = False Then
       ToastMessageShow("Please allow connection and click again.", True)
       manager.RequestPermission(device)
     Else
       usbserial.Initialize("serial", device, -1)
       usbserial.BaudRate = 115200
       usbserial.DataBits = usbserial.DATA_BITS_8
       usbserial.StartReading
     End If
   End If
End Sub

Private Sub serial_DataAvailable (Buffer() As Byte)
   Log("New data: " & bc.HexFromBytes(Buffer))
End Sub

SetFlowControl is only implemented for CP2102, FTDI and CH34x chips.

Updates

V1.12 - BUFFER_READ_SIZE / BUFFER_WRITE_SIZE fields. Default value is 16 * 1024. You can change these values before initializing the object to change the internal buffers sizes.

 

[Emanuel Straub]

Yes, it's only happen when both devices are connected.

Do i need it when i only want to do a write on it? I'll give it a try.

 

[Erel]

It is possible that the hardware is limited to a single device.

 

[Emanuel Straub]

I dont know if it is limited to a single device.
It's working for a few seconds and then application freezes for some seconds.
After that the application freeze totaly and androids crash and reboots.

And Some times the application freeze totaly and after i disconnected the usb cable the application recovers.

 

[Thuong]

Thank Erel
Good job !
I've done with China's Arduino Nano (chip CH340)

 

[Ferraz71]

Does the library already support the microchip MCP2221 ?

 

[Erel]

You can see the list of supported chips in the first post.

 

[entolium]

Thank Erel! Great work!

I'm using with Arduino and works fine, but I have a problem. I send an instruction, and I need to wait for the response.
If use a "Do while" with Doevents, the "DataAvailable" event don't raise... (?)
Without the "Do While", the program runs perfect.

my code is:

Sub Enviar
Respuesta=""
usbserial.Write(bc.StringToBytes(txtEnviar.Text & CRLF,"UTF8"))
Do While Respuesta=""
DoEvents
Loop
txtRespuesta.Text=Respuesta
End Sub

Sub serial_DataAvailable (Buffer() As Byte)
Respuesta=bc.StringFromBytes(Buffer,"UTF8")
End Sub


Any idea?

 

[Erel]

Please start a new thread for this question.

 

[entolium]

Hi Erel,

I'm not sure where is the best place for this question .
The code is very simple, but only works when I don't use the "Do while". I think could be a problem with the library.

 

[Erel]

The best place for all questions is: https://www.b4x.com/android/forum/forums/android-questions.26/

 

[Erel]

V1.10 is attached to the first post. It it based on the latest version of the open source project: https://github.com/felHR85/UsbSerial

 

[red30]

Hi!
I get the array of data:
Sub fel_DataAvailable (Buffer() As Byte)

End Sub
The received array consists of 8 bytes: Buffer(1),Buffer(2), etc. I need to work with each bit of each byte separatly ( f.e. I need to get the 5th bit of the Buffer(1)). How can I do it?
Thank you for the responce.

 

[Erel]

Please start a new thread for this in the questions forum. This question is not specific to felUsbSerial.

 

[red30]

Your programme works well but I have a question.
When I connect to the device and exchange data and take the USB OTG cable out, the app closes with an error.

Can I write a tost message that "USB cable is taken out" and to relaunch the app automatically?

 

[Erel]

Can you post the error message from the logs?

 

[red30]

Can you post the error message from the logs?

I can not give Logs, since I can not connect wirelessly B4A for debugging ...
I'm using the USB cable for debug, and since I'm working with otg, I can not connect simultaneously debugging and the device which i am working with

Tablet RoverPad Sky Glory S7, android 5.1. There is a otg support, a flash card is supported too, a mouse too. But when i try to connect my device UsbDevices.Length = 0. Why?

 

[Erel]

I can not give Logs, since I can not connect wirelessly B4A for debugging ...

Why can't you connect?

But when i try to connect my device UsbDevices.Length = 0. Why?

This means that the OS didn't recognize any connected USB device.

 

[red30]

Why can't you connect?

The tablet is connected to WF router which is connected to switch which is connected to server. The computer is connected to the server too. I run B4A-bridge and push "Start Wireless" and then in "My IP" my router's IP is written. In B4A i write this adress and push Connect, then write this IP and it replies : Ping failed, TimeOut.
I cant understand why...

This means that the OS didn't recognize any connected USB device.

No, it doesnt recognise only this device, flash cards, mouses etc are ok.
I install USB host controller from Playmarket and my devise is in the list of otg devices there, so its VID and PID are correct there.

 

[Erel]

I meant that the OS didn't recognize the connected device.
You can try this "fix": https://www.b4x.com/android/forum/t...rs232-adaptor-driver.11449/page-3#post-121125

 

[red30]

I meant that the OS didn't recognize the connected device.
You can try this "fix": https://www.b4x.com/android/forum/t...rs232-adaptor-driver.11449/page-3#post-121125

I did everything as written. On the same device all at once earned (RoverPad Sky Glory S7). In a second (Explay Scream 3G) everything remains the same .. Why?

Today i got the same error on explay Explay Scream 3G. It reads all otg device, but when i connect my : UsbDevices.Length = 0 . The programm usb host controller also sees my device