WSMBS Modbus Master RTU/ASCII Control for .NET

WSMBS is a powerful and simple to use .Net Control that makes it easy to access data from a Modbus slave device connected to the PC's serial port. Simply drop the Control on your form and talk to your device with your VB.NET, C# or Managed C++.
See the Quick Start Guide.

Download trial version
The trial version is a full featured version with a 30 min connection limit.

You may redistribute the wsmbt.dll assembly with your application program unlimited without any royalty.

Supported protocol variants:

  • Modbus RTU
  • Modbus ASCII


  • 01: Read coil status
  • 02: Read input status
  • 03: Read holding registers
  • 04: Read input registers
  • 05: Force single coil
  • 06: Preset single register
  • 15: Force multiple coils
  • 16: Preset multiple registers
  • 17: Report Slave ID.
  • 22: Mask write register
  • 23: Read/Write registers

User defined functions:

  • Read User Defined Coils
  • Read User Defined Registers
  • Write User Defined Coils
  • Write User Defined Registers


Int16[] Registers = new Int16[10];
WSMBS.Result Result;
Result = wsmbsControl1.ReadHoldingRegisters(1, 0, 10, Registers);

Visual Basic
Dim Registers(10) As Short
Dim Result As WSMBS.Result
Result = WsmbtControl1.ReadHoldingRegisters(1, 0, 10, Registers)

array<Int16>^ Registers = gcnew array<Int16>(10);
WSMBS::Result Result;
Result = wsmbtControl1->ReadHoldingRegisters(1, 0, 10, Registers);