ModSimCE...
Application Description

Put the full power of the Windows Operating System in your shirt pocket and take it to the factory floor for testing and verification of modbus devices. ModSimCE utilizes the same "look and feel" of it's Win32 counterpart to allow you to easily connect to a modbus master device for simulation of data points from one or more modbus slave devices. ModSimCE supports both the RTU and ASCII transmission modes of operation and may be used to simulate all four types of modbus data, (INPUT STATUS, COIL STATUS, INMPUT REGISTER and HOLDING REGISTER). ModSimCE supports modbus function codes 01-06, 08, 15 & 16. The basic operation of the application is depicted below:

These two screen shots show the ModSimCE application display of holding register and coil status data. Up to 1000 data points of each type may be defined by the user for access from an attached modbus master device. Separate menu commands allow you to specify the slave address and range of addresses to simulate for each data type.

You may also write a pattern to a block of simulated data by using the following dialog:

Menu options allow register values to be displayed in a variety of formats. Both RTU and ASCII transmission modes are supported, and any available COM port may be used, including the IR port.