Modbus Slave allows you to simulate up to 32 slave devices on 32 windows. This simulating tool will speed up your PLC programming. Test and program your slave devices before they arrive from the supplier. The master application can access any data contained in an open document. Modbus Poll has the same user interface. Support functions 01, 02, 04, 05. 06, 15, 16, 22, 23.