Installing the modbus RTU library for Android is straightforward. Once you decided which version to use (release or debug), follow these steps:

  • Copy the wrapper BiemmeModbus.jar into \libs folder of your Android project
  • Copy the native modbus RTU library into \libs\armeabi (eventually create it if it does not exist)
  • Refresh your project (not needed if you now create a new fresh project).
  • Use the following statement for importing the package from your activity:
import com.biemme.modbus.*;

That's it! Use the library as your needs. For instance, you can add the following statements for reading the first 10 registers from node 1.

  protected void onResume() {
	int slave_id = 1;	//slave id device number
	int fid      = 0; 	//file handler serial port
	int start_ad = 0;
	int regs     = 10;	//number of registers to read
	int [] hr = new int[20];
	//serial opening with baudrate 38400 bps and 40000ns as timeout
	fid 	  = ModbusLib.openCom(38400, 40000, 40000);
	//Logs the fid, use adb logcat
	ModbusLib.ReadHoldingRegisters(fid, slave_id, start_ad, regs, hr);
	for (int i = 0; i <= (regs-1); i++){
		Log.d("Reg Value =",String.valueOf(hr[i]));