Important!!! If you selected "Use Multiple Register Write" mode then AVReporter Modbus Communication Tester uses Preset Multiple Registers Function. Device Type: 01 ModBus TCP Device - 06 Preset Single Register 02 Modbus RTU Device - 06 Preset Single Register 03 ModBus TCP Device (Use Multiple Register Write) - 16 (10 Hex) Preset Multiple Registers 04 ModBus RTU Device (Use Multiple Register Write) - 16 (10 Hex) Preset Multiple Registers