New errors after getting the lenovo tab

java.lang.OutOfMemoryError
at anywheresoftware.b4a.randomaccessfile.AsyncStreams $AIN.run(AsyncStreams.java:172)
at java.lang.Thread.run(Thread.java:856)

Sub AStream_NewData (Buffer() As Byte) 'Serial Receive interrupt routine
If RxEnabled = False Then 
   Return
End If
RxPacket = RxPacket & BytesToString(Buffer, 0, Buffer.Length, "UTF8")
'Since we arnt using Prefix mode, The entire packet may not have arrived when this event is triggered. 
'Since we are doing length and checksummed packets, We test for a valid packet and length before releasing the packet.  
If Len(RxPacket) > 4 Then
   PacketLength = Len(RxPacket) / 2   'Length of packet
   TestLength = HexString(Mid(RxPacket, 3, 2)) 'Send Length byte
   TestLength = TestLength + 4       'Include header byte, Length byte, checksum byte, and character return (AVR Print) as part of the length. Ensure full data packet recpetion. 
   If TestLength = PacketLength Then
      RxHandler
      RxPacket = ""
   End If
End If
Return
End Sub

'We Drop here when a command process has succeeded, and no data has been requested or supported.
Sub Rsp90()
Prefixheader(1) = 0
Prefixheader(2) = 0
Prefixheader(3) = 0

If Ismaster = 0 Then
   If Slaveaddress <> 0 Then                                'If this board is configured as slave, we DONT respond.
      Reset Flags.4
      Reset Flags.6
      Exit Sub
   End If
End If

Packetbuffer = "120190"
Call Dochecksum
Packetbuffer = Packetbuffer + Hex(checksm)
Length = Len(packetbuffer)
Length = Length + 2
Prefixheader(4) = Length
Printbin Prefixheader(1) ; 4
Print Packetbuffer

Reset Flags.4
Reset Flags.6
End Sub