Android Question Translate SDK RFID Bluetooth Reader to B4A

[Christian García S.]

Hello Everyone,

I was making a connection with a Bluetooth RFID Reader via bluetooth admin and serial, as described in the following tutorial.

https://www.b4x.com/android/forum/threads/android-bluetooth-bluetoothadmin-tutorial.14768/

But I receive a timeout with the following error:

java.io.IOException: read failed, socket might closed or timeout, read ret: -1
    at android.bluetooth.BluetoothSocket.readAll(BluetoothSocket.java:916)
    at android.bluetooth.BluetoothSocket.readInt(BluetoothSocket.java:928)
    at android.bluetooth.BluetoothSocket.connect(BluetoothSocket.java:536)
    at anywheresoftware.b4a.objects.Serial$1.run(Serial.java:157)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:428)
    at java.util.concurrent.FutureTask.run(FutureTask.java:237)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1133)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:607)
    at java.lang.Thread.run(Thread.java:762)
connected: false

The reader comes with its own SDK, they send you the sources and an apk so you can make the connection with your own APP, I have tried that app on the phone and it works, connects correctly and reads the rfid tags.

I have read the java code of that sdk, but I can not identify any parameters to change in the connection so that it is successful with bluetooth admin.

I do not know if you can help me check the connection of that SDK and try to translate it into B4A code so I can exploit the functionality of the RFID and the full power of B4A.

Attached the link sdk https://goo.gl/nP8LBb, can you help me to review those sources ??? I have reviewed the original sources but I can not identify which parameter is different to change.

Also attached a small video https://goo.gl/ayPjKJ testing the application that comes with the reader and that is the application of that SDK to see how it works.

Thank you very much in advance.

 

[Christian García S.]

Hello,

After reading some posts I tried with BLE 2 now I and can connect with reader.

I was reading manual and I need send EPC C1G2 COMMAND (manual https://goo.gl/nPi8rK) for getting RFID tags.

The command I have to send, first to get Reader Info:

Sub Command_GetReaderInfo

 
    Dim Msg() As Byte
 
'    aStream.Write(Array As Byte (2,Asc("?"),Asc("s"),Asc("t"),3,Asc("3"),Asc("5")))
    Dim cmdSecv As List
 
    cmdSecv.Initialize
                      
    cmdSecv.Add(0x04)
    cmdSecv.Add(0xFF)
    cmdSecv.Add(0x21)
    cmdSecv.Add(0x19)
    cmdSecv.Add(0x95)
 
    Msg = ListToBytes(cmdSecv) 
      
    manager.WriteData("0000180a-0000-1000-8000-00805f9b34fb","00002a50-0000-1000-8000-00805f9b34fb",Msg)
End Sub

based in this code from SDK

public static int GetReaderInfo(byte[]Version,byte[] Power,byte[] Fre)
{
byte[] Msg = new byte[6];
Msg[0] = 0x04;
Msg[1] = (byte)0xFF;
Msg[2] = 0x21;
Msg[3] = 0x19;
Msg[4] = (byte)0x95;
CmdTime=500;
MyService.target_chara.setValue(Msg);
ArrayClear(RecvBuff,5000);
RecvLength=0;
MyService.RecvString="";
mBluetoothLeService.writeCharacteristic(MyService.target_chara);
if(GetData()==0){
       ComAddr = RecvBuff[1];
       Version[0] = RecvBuff[4];
       Version[1] = RecvBuff[5];
       Power[0] = RecvBuff[10];
       Fre[0] = RecvBuff[8];
       Fre[1] = RecvBuff[9];
          return RecvBuff[3];
       }
return -1;
}

But now I do not know which Characteristic I have to use, I get error message.

I wrote this code based in this example https://www.b4x.com/android/forum/threads/ble-2-bluetooth-low-energy.59937/#post-381524 for knowing the characteristics.

Sub Manager_DataAvailable (ServiceId As String, Characteristics As Map)
    Log("***********************************")
    Log("Serviceid: "&ServiceId & " Char: "&Characteristics)
  
  
    For Each k As String In Characteristics.Keys
'        Log(k)
        Dim data1() As Byte = Characteristics.get(k)
        Dim bc As ByteConverter
'        Log("Data")
        Log("Key: " & k & " -> Value: " & bc.HexFromBytes(data1))  
      
        PrintCharProperties(k, manager.GetCharacteristicProperties(ServiceId, k))
          
    Next          
  
    CallSub3(Main, "DataAvailable", ServiceId, Characteristics)
End Sub

Sub PrintCharProperties(Characteristic As String, Properties As Int)
    Log($"${Characteristic} Properties:"$)
    Dim props As Map = CreateMap(1: "Broadcast", 2: "Read", 4: "WriteWithoutResponse", 8: "Write", _
     0x10: "Notify")
    For Each key As Int In props.Keys
        If Bit.And(Properties, key) <> 0 Then Log(props.Get(key))
    Next
End Sub

This is Output:

***********************************
***********************************
Serviceid: 00001801-0000-1000-8000-00805f9b34fb Char: (MyMap) {00002a05-0000-1000-8000-00805f9b34fb=[B@bd065c8}
Key: 00002a05-0000-1000-8000-00805f9b34fb -> Value:
00002a05-0000-1000-8000-00805f9b34fb Properties:
***********************************
Serviceid: 00001800-0000-1000-8000-00805f9b34fb Char: (MyMap) {00002a00-0000-1000-8000-00805f9b34fb=[B@2202586, 00002a01-0000-1000-8000-00805f9b34fb=[B@ec2fe47, 00002a02-0000-1000-8000-00805f9b34fb=[B@46a1674, 00002a04-0000-1000-8000-00805f9b34fb=[B@5bb179d, 00002a03-0000-1000-8000-00805f9b34fb=[B@2491412}
Key: 00002a00-0000-1000-8000-00805f9b34fb -> Value: 554254313735323939313742
00002a00-0000-1000-8000-00805f9b34fb Properties:
Read
Key: 00002a01-0000-1000-8000-00805f9b34fb -> Value: 0000
00002a01-0000-1000-8000-00805f9b34fb Properties:
Read
Key: 00002a02-0000-1000-8000-00805f9b34fb -> Value: 00
00002a02-0000-1000-8000-00805f9b34fb Properties:
Read
Write
Key: 00002a04-0000-1000-8000-00805f9b34fb -> Value: 5000A0000000E803
00002a04-0000-1000-8000-00805f9b34fb Properties:
Read
Key: 00002a03-0000-1000-8000-00805f9b34fb -> Value:
00002a03-0000-1000-8000-00805f9b34fb Properties:
Write
***********************************
Serviceid: 0000180a-0000-1000-8000-00805f9b34fb Char: (MyMap) {00002a23-0000-1000-8000-00805f9b34fb=[B@52737e3, 00002a24-0000-1000-8000-00805f9b34fb=[B@14c25e0, 00002a25-0000-1000-8000-00805f9b34fb=[B@c369099, 00002a26-0000-1000-8000-00805f9b34fb=[B@2a05f5e, 00002a27-0000-1000-8000-00805f9b34fb=[B@c0b6f3f, 00002a28-0000-1000-8000-00805f9b34fb=[B@67dc00c, 00002a29-0000-1000-8000-00805f9b34fb=[B@9569d55, 00002a2a-0000-1000-8000-00805f9b34fb=[B@28f136a, 00002a50-0000-1000-8000-00805f9b34fb=[B@cd1c05b}
Key: 00002a23-0000-1000-8000-00805f9b34fb -> Value: 3F05110000831500
00002a23-0000-1000-8000-00805f9b34fb Properties:
Read
Key: 00002a24-0000-1000-8000-00805f9b34fb -> Value: 4D6F64656C204E756D62657200
00002a24-0000-1000-8000-00805f9b34fb Properties:
Read
Key: 00002a25-0000-1000-8000-00805f9b34fb -> Value: 53657269616C204E756D62657200
00002a25-0000-1000-8000-00805f9b34fb Properties:
Read
Key: 00002a26-0000-1000-8000-00805f9b34fb -> Value: 4669726D77617265205265766973696F6E00
00002a26-0000-1000-8000-00805f9b34fb Properties:
Read
Key: 00002a27-0000-1000-8000-00805f9b34fb -> Value: 4861726477617265205265766973696F6E00
00002a27-0000-1000-8000-00805f9b34fb Properties:
Read
Key: 00002a28-0000-1000-8000-00805f9b34fb -> Value: 536F667477617265205265766973696F6E00
00002a28-0000-1000-8000-00805f9b34fb Properties:
Read
Key: 00002a29-0000-1000-8000-00805f9b34fb -> Value: 4D616E756661637475726572204E616D6500
00002a29-0000-1000-8000-00805f9b34fb Properties:
Read
Key: 00002a2a-0000-1000-8000-00805f9b34fb -> Value: FE006578706572696D656E74616C
00002a2a-0000-1000-8000-00805f9b34fb Properties:
Read
Key: 00002a50-0000-1000-8000-00805f9b34fb -> Value: 010D0000001001
00002a50-0000-1000-8000-00805f9b34fb Properties:
Read
***********************************
Serviceid: 0000ffe0-0000-1000-8000-00805f9b34fb Char: (MyMap) {0000ffe1-0000-1000-8000-00805f9b34fb=[B@f4cd0f8}
Key: 0000ffe1-0000-1000-8000-00805f9b34fb -> Value: 06
0000ffe1-0000-1000-8000-00805f9b34fb Properties:
Read
WriteWithoutResponse
Write
Notify

I read this in SDK, but I don't have this variable mBluetoothGatt in B4A.

public void getCharacteristicDescriptor(BluetoothGattDescriptor descriptor)
    {
         if (mBluetoothAdapter == null || mBluetoothGatt == null) {
             Log.w(TAG, "BluetoothAdapter not initialized");
             return;
         }
        
         mBluetoothGatt.readDescriptor(descriptor);
    }

Can someone help me know what characteristic I should use for each option???

EPC C1G2 COMMAND

1. Inventory
2. Read Data
3. Write Data
4. Write EPC
5. etc.

Thanks in advance.

 

[Erel]

What is MyService.target_chara in the Java code?

 

[Christian García S.]

Thanks Erel,

In sdk code is

public static BluetoothGattCharacteristic target_chara=null;

I attached myservice.java code and full code (http://goo.gl/nP8LBb)

Thanks

 

[Erel]

target_chara equals to HEART_RATE_MEASUREMENT

0000ffe1-0000-1000-8000-00805f9b34fb

 

[Christian García S.]

Thanks Erel,

Right, that was the characteristic now I'm trying to write the values to that characteristic.

I am using the following function:

Sub Command_GetReaderInfo
 
    Dim Msg() As Byte
    Dim ServiceId As String              = "0000ffe0-0000-1000-8000-00805f9b34fb"
    Dim Characteristic As String          = "0000ffe1-0000-1000-8000-00805f9b34fb"
 
    Log("Write data: ")

    Msg = Array As Byte (0x04,0xFF,0x21,0x19,0x95)
 
    manager.WriteData(ServiceId,Characteristic,Msg)
    ReadData
End Sub

Based on the function of the SDK:

public static int GetReaderInfo(byte[]Version,byte[] Power,byte[] Fre)
{
byte[] Msg = new byte[6];
Msg[0] = 0x04;
Msg[1] = (byte)0xFF;
Msg[2] = 0x21;
Msg[3] = 0x19;
Msg[4] = (byte)0x95;
CmdTime=500;
MyService.target_chara.setValue(Msg);
ArrayClear(RecvBuff,5000);
RecvLength=0;
MyService.RecvString="";
mBluetoothLeService.writeCharacteristic(MyService.target_chara);
if(GetData()==0){
       ComAddr = RecvBuff[1];
       Version[0] = RecvBuff[4];
       Version[1] = RecvBuff[5];
       Power[0] = RecvBuff[10];
       Fre[0] = RecvBuff[8];
       Fre[1] = RecvBuff[9];
          return RecvBuff[3];
       }

But when I use function ReadData

Public Sub ReadData
    For Each s As String In ConnectedServices
        manager.ReadData(s)
     
    Next
End Sub

You can guide me if I am writing the values correctly (0xFF and 0x95 In SDK are (byte)0xFF, (byte)0x95) or if I have to obtain them in another way.

I receive empty values:

Write data:
Serviceid: 00001801-0000-1000-8000-00805f9b34fb Char: (MyMap) {00002a05-0000-1000-8000-00805f9b34fb=[B@960dee6}
***********************************
Key: 00002a05-0000-1000-8000-00805f9b34fb -> Value:
Key: 00002a05-0000-1000-8000-00805f9b34fb -> Value:
00002a05-0000-1000-8000-00805f9b34fb Properties:

Thank you.

 

[Christian García S.]

If I put

manager.WriteData(ServiceId,Characteristic,Msg)
manager.SetIndication(ServiceId, Characteristic,True)

I receive this

Write data:
Setting descriptor. Success = true
writing descriptor: true
Serviceid: 00001801-0000-1000-8000-00805f9b34fb Char: (MyMap) {00002a05-0000-1000-8000-00805f9b34fb=[B@8d15c0e}
***********************************
Key: 00002a05-0000-1000-8000-00805f9b34fb -> Value:
Key: 00002a05-0000-1000-8000-00805f9b34fb -> Value:
Serviceid: 0000ffe0-0000-1000-8000-00805f9b34fb Char: (MyMap) {0000ffe1-0000-1000-8000-00805f9b34fb=[B@ff7443c}
***********************************
Key: 0000ffe1-0000-1000-8000-00805f9b34fb -> Value: 110021000201100231801A0A010100004231

Is this (110021000201100231801A0A010100004231) the answer ??? If the answer is YES, how can I decode these values? In sdk there are some functions GetData,
getCRC, CheckCRC

Thanks

 

[Erel]

    Msg = Array As Byte (0x04,0xFF,0x21,0x19,0x95)
 
    manager.WriteData(ServiceId,Characteristic,Msg)

This code correctly writes the 5 bytes.

Is this (110021000201100231801A0A010100004231) the answer ???

This is the characteristic value.

If the answer is YES, how can I decode these values?

You will need to go over the SDK code and do the same thing in your B4A code. Each implementation is different.

 

[Christian García S.]

Thanks Erel, now I can read and write characteristics.

I am searching how to read data, in a post https://www.b4x.com/android/forum/threads/rfid-reader-connection.73322/#post-465827 you wrote "Make sure to initialize AsyncStreams in non-prefix mode"

I am trying the way to connect AsyncStreams, but I just found examples with Bluetooth Admin and serial.

I tried with serial, but the connection gives error.

Sub Process_Globals

Public manager As BleManager2
Dim BTConnection As Serial
Dim Astream As AsyncStreams

End Sub

Sub Manager_DeviceFound (Name As String, Id As String, AdvertisingData As Map, RSSI As Double)
    Log("Found: " & Name & ", " & Id & ", RSSI = " & RSSI & ", " & AdvertisingData)
manager.StopScan
        manager.Connect2(Id, False) 'disabling auto connect can make the connection quicker
        BTConnection.Initialize("RFIDreader")
        BTConnection.Connect(Id)
End Sub

Sub RFIDreader_Connected (Success As Boolean)
    If Success Then
        Log("RFID conectado")
        Astream.Initialize(BTConnection.InputStream,Null,"RFIDreaderAs")
    Else
        ToastMessageShow("RFID no encontrado...",False)
    End If
End Sub

Can you help me with where or how I can get the data, with asyncstreams or by other way.

Thanks

 

[Erel]

Please start a new thread for a new question.

 

[Christian García S.]

Thanks Erel,

I'm not sending the proper command to read the inventory, can you help me review it please ????

Manual is this https://goo.gl/nPi8rK, and java code (https://goo.gl/nP8LBb) is:

public static void getCRC(byte[] data,int Len)
{
int i, j;
int current_crc_value = 0xFFFF;
for (i = 0; i <Len ; i++)
{
    current_crc_value = current_crc_value ^ (data[i] & 0xFF);
    for (j = 0; j < 8; j++)
    {
        if ((current_crc_value & 0x01) != 0)
            current_crc_value = (current_crc_value >> 1) ^ 0x8408;
        else
            current_crc_value = (current_crc_value >> 1);
    }
}
data[i++] = (byte) (current_crc_value & 0xFF);
data[i] = (byte) ((current_crc_value >> 8) & 0xFF);
}
public static int Inventory_G2(byte QValue,byte Session, byte AdrTID, byte LenTID,
             byte TIDFlag,int[] CardNum,byte[] EPCList,int[] EPCLength) {
         byte[] Msg=new byte[10];
         Msg[1]=(byte)(ComAddr & 255);
         Msg[2]=1;
         Msg[3]=QValue;
         Msg[4]=Session;
         if(TIDFlag==0)
         {
             Msg[0]=6;
             getCRC(Msg,5);
         }
         else
         {
             Msg[0]=8;
             Msg[5]=AdrTID;
             Msg[6]=LenTID;
             getCRC(Msg,7);
         }
         MyService.target_chara.setValue(Msg);;
         ArrayClear(RecvBuff,300);
         RecvLength=0;
         MyService.RecvString="";
         mBluetoothLeService.writeCharacteristic(MyService.target_chara);
         Log.d("Write data:", "AAAAAAAAAAAAAAAAA");
         if(GetInventoryData()==0)
         {
                byte[]szBuff=new byte[3000];
                byte[]szBuff1=new byte[3000];
                memcpy(RecvBuff,0,szBuff,0,RecvLength);
                int Nlen=0;
                while(RecvLength>0)
                {
                    int nLenszBuff=(szBuff[0]&255)+1;
                    if((szBuff[3]==0x01)||(szBuff[3]==0x02)||(szBuff[3]==0x03)||(szBuff[3]==0x04))
                    {
                        //*Ant=szBuff[4];
                        CardNum[0]+=(szBuff[5]&255);
                        memcpy(szBuff,6,szBuff1,Nlen,(szBuff[0]&255)-7);   
                        Nlen+=((szBuff[0]&255)-7);
                        if((RecvLength-(szBuff[0]&255)-1)>0)
                        {
                            byte[]daw=new byte[3000];
                            memcpy(szBuff,(szBuff[0]&255)+1,daw,0,RecvLength-(szBuff[0]*255)-1);
                            ArrayClear(szBuff,3000);
                            memcpy(daw,0,szBuff,0,RecvLength-(szBuff[0]*255)-1);
                        }
                    }
                    RecvLength=RecvLength-nLenszBuff;
                }
                memcpy(szBuff1,0,EPCList,0,Nlen);
                EPCLength[0]=Nlen;
                return  szBuff[3];
         }
         return 0x30;
    }

These is my code:

Sub Command_GetReaderInfo   
    Dim Msg() As Byte

    Log("Write data: ")

    Msg = Array As Byte (0x04, 0xFF,0x21,0x19,0x95)
 
    manager.WriteData(ServiceId_G,Characteristic_G,Msg)
    manager.SetNotify(ServiceId_G,Characteristic_G, True)
    SetCommand = 1
    ReadData
End Sub

Sub Command_Inventory_G2
 
    Dim Msg() As Byte

    Log("Write data: ")

    'Msg = Array As Byte (0,1,2,3,4)
     Msg = Array As Byte (0x06,ComAddr & 255 ,0x01,0x04,0x00,0x00,0x00)
 
    manager.WriteData(ServiceId_G,Characteristic_G,Msg)
    manager.SetNotify(ServiceId_G,Characteristic_G, True)
    SetCommand = 2
    ReadData
End Sub

Sub memcpy (SourceByte() As Byte, StartBit_1 As Int, StartBit_2 As Int, Length As Int) As Byte()
    Dim TargetByte(Length) As Byte
 
    For m = 0 To Length-1
        TargetByte(StartBit_1+m) = SourceByte(StartBit_1+m)
    Next
 
    Return TargetByte
End Sub

Sub Manager_DataAvailable (ServiceId As String, Characteristics As Map)
 
    Log("Serviceid: "&ServiceId & " Char: "&Characteristics)
 
    For Each k As String In Characteristics.Keys
        Dim data1() As Byte = Characteristics.get(k)
        Dim bc As ByteConverter
        Log("***********************************")
        Log("Key: " & k & " -> Value: " & bc.HexFromBytes(data1))
        Log("Key: " & k & " -> Value: " & data1)

        If ServiceId = ServiceId_G And k = Characteristic_G Then
            Dim RecvBuff(), Version(2), PowerV(1), Fre(2) As Byte
   
            If SetCommand = 1 Then
                RecvBuff = memcpy(data1,0,0,data1.Length)
                ComAddr = RecvBuff(1)
                Version(0) = RecvBuff(4)
                Version(1) = RecvBuff(5)
                PowerV(0) = RecvBuff(10)
                Fre(0) = RecvBuff(8)
                Fre(1) = RecvBuff(9)
                Command_Inventory_G2
            End If
   
        End If   
 
'        PrintCharProperties(k, manager.GetCharacteristicProperties(ServiceId, k))
    Next       
    CallSub3(Main, "DataAvailable", ServiceId, Characteristics)
End Sub

Thanks

 

[guilhermefilippo]

Hello @Christian García S.

I am lost with that same SDK.
Did you solve your doubts?
I already spent a week trying to solve it.

Thank you,
Guilherme

PS: I'm trying to translate that SDK using Flutter and the FlutterBlue plugin. Although it is different technology, my doubts are similar to yours.