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.

 

[Jaames]

WoW, so simple.. Thanks.

 

[Abílio Magalhães]

Dear Erel,

This library is working perfectly!!!

Thank you for so dedicated support.

I'm very happy with Basic4Android. it had proveed to be the best RAD tool for developing in a large and complex Android app.

Kind regards,
Abilio

 

[Toley]

Thank you Erel, very usefull one since it supports CH340. But do you think it can be used with AsyncStreams since it don't have any GetInputStream and GetOutputStream methods?

 

[Erel]

You don't need to use AsyncStreams here. It raises a similar NewData event.

 

[Kurt McCullum]

You don't need to use AsyncStreams here. It raises a similar NewData event.

I've only been using B4a for about a week so I may be missing something here. I took the code from above and used it in a new project. I can write data using usbserial.write but the NewData event is never fired when I send data to the device.

I noticed in your code that it is serial_NewData, should it be usbserial_NewData.

I'm using an FTDI usb to serial device.

Thanks

Kurt

 

[Kurt McCullum]

I've only been using B4a for about a week so I may be missing something here. I took the code from above and used it in a new project. I can write data using usbserial.write but the NewData event is never fired when I send data to the device.

Kurt

I just figured it out. The event name should be serial_dataavailable. Once that change is made to your code it works great.

Kurt

 

[Erel]

V0.91 is available in the first post. The event name was incorrect. As @Kurt McCullum wrote above, it should be DataAvailable.

 

[mtselection]

Hello Erel,

I'm using this library instead of USBSerial, but I need to use the RTS control. I'm using the property FlowControl with FLOW_CONTROL_RTS_CTS but seems not to work. For the reference site is a function in development. You know if this is possible?

Thank you

Maurizio

 

[Erel]

Which type of chip are you using?

 

[mtselection]

PL2303HX

 

[Erel]

I've checked the internal library source code.

The SetFlowControl is only implemented for the following chips: CP2102 and FTDI.

I will add a message about it in the documentation.

 

[mtselection]

Thanks Erel for your support.

Maurizio

 

[Kurt McCullum]

Is it possible to check the status of the DSR line with this library? I have a situation where a remote device sets the DSR line whenever it opens its serial port and my app needs to know when there is a change so I can start sending data. It's a bit different than a flow control using DSR since I'm only checking the status of it.

Kurt

 

[Erel]

No. It is not possible.

 

[Kurt McCullum]

Thanks Erel. I thought it was possible with GetDSR() function but when I went and looked at the code I noticed the //TODO comment and no code. I suppose that's a future enhancement.

 

[Wal]

I use this code with a CDC-Device:

Sub Process_Globals
    Private usbserial As felUsbSerial
    Private manager As UsbManager
    Private UsbPid As Int = 0xa
    Private UsbVid As Int = 0x4D8
   
    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
    Dim UsbDevices() As UsbDevice
    UsbDevices = manager.GetDevices
    If UsbDevices.Length = 0 Then
        ToastMessageShow("No connected usb devices.", True)           
    Else
        For z = 0 To UsbDevices.Length - 1
            Dim UsbDvc As UsbDevice
            UsbDvc = UsbDevices(z)
            Log("USBDeviceNr. " & z & " --- UsbPid = " & UsbDvc.ProductId)
             If (UsbDvc.ProductId = UsbPid) And (UsbDvc.VendorId = UsbVid) Then               
                If manager.HasPermission(UsbDvc) = False Then
                       ToastMessageShow("Please allow connection and click again.", True)
                       manager.RequestPermission(UsbDvc)
                 Else   
                    If usbserial.IsInitialized Then usbserial.Close
                    Log("Initialize USBDeviceNr. " & z )
                    usbserial.Initialize("serial", UsbDvc, -1)  <-- Line55
                       usbserial.BaudRate = 57600
                       usbserial.DataBits = usbserial.DATA_BITS_8
                       Set232(usbserial, True, False)
                       usbserial.StartReading
                End If
                Exit
            End If
        Next
    End If
End Sub

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

Sub Waitms(ms As Int)
   Dim Ti As Long
   Ti = DateTime.Now + (ms)
   Do While DateTime.Now < Ti
      DoEvents
   Loop
End Sub

Sub Set232(USB As felUsbSerial, RTSBool As Boolean, DTRBool As Boolean)
    Dim r As Reflector
    r.Target = USB
    r.Target = r.getField("driver")
    r.RunMethod2("setRTS", RTSBool, "java.lang.boolean")
    r.RunMethod2("setDTR", DTRBool, "java.lang.boolean")
    Waitms(2000)
End Sub

Error :

Installing file.
PackageAdded: package:b4a.example
** Service (starter) Create **
** Service (starter) Start **
** Activity (main) Create, isFirst = true **
** Activity (main) Resume **
USBDeviceNr. 0 --- UsbPid = 33145
USBDeviceNr. 1 --- UsbPid = 10
** Activity (main) Pause, UserClosed = false **
** Activity (main) Resume **
USBDeviceNr. 0 --- UsbPid = 33145
USBDeviceNr. 1 --- UsbPid = 10
Initialize USBDeviceNr. 1
Error occurred on line: 55 (Main)
java.lang.RuntimeException: Error opening serial device.
    at anywheresoftware.b4a.objects.usb.felUsbSerial.Initialize(felUsbSerial.java:60)
    at b4a.example.main._btnconnect_click(main.java:447)
    at java.lang.reflect.Method.invokeNative(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:515)
    at anywheresoftware.b4a.shell.Shell.runMethod(Shell.java:697)
    at anywheresoftware.b4a.shell.Shell.raiseEventImpl(Shell.java:339)
    at anywheresoftware.b4a.shell.Shell.raiseEvent(Shell.java:246)
    at java.lang.reflect.Method.invokeNative(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:515)
    at anywheresoftware.b4a.ShellBA.raiseEvent2(ShellBA.java:134)
    at anywheresoftware.b4a.BA.raiseEvent2(BA.java:157)
    at anywheresoftware.b4a.BA.raiseEvent(BA.java:153)
    at anywheresoftware.b4a.objects.ViewWrapper$1.onClick(ViewWrapper.java:78)
    at android.view.View.performClick(View.java:4443)
    at android.view.View$PerformClick.run(View.java:18443)
    at android.os.Handler.handleCallback(Handler.java:733)
    at android.os.Handler.dispatchMessage(Handler.java:95)
    at android.os.Looper.loop(Looper.java:136)
    at android.app.ActivityThread.main(ActivityThread.java:5017)
    at java.lang.reflect.Method.invokeNative(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:515)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
    at dalvik.system.NativeStart.main(Native Method)
** Activity (main) Pause, UserClosed = true **

Can you help me ?

 

[Erel]

Check the unfiltered logs. There might be more information there.

 

[Erel]

I don't think that it is related. To actually see the unfiltered logs you will need to connect with usb debug mode. Now that I think about it, it is probably not really possible in this case.

You can try to explicitly set the interface index (instead of setting it to -1). Go over the interfaces and find the correct one.

The felUsbSerial library searches for an interface with interface class of 10.

 

[Wal]

I was just wondering that the FTDI device emerges, although the USBPid 10's.

You can try to explicitly set the interface index (instead of setting it to -1). Go over the interfaces and find the correct one.

That's what I've done, to no avail.

That's not bad, USB Serial Lib works.
I wanted to test only the new Lib.