Software - Testing and Simulation
ModSlaveSim is a programmable simulator that enables realistic simulation of a Modbus server in its environment. Connect your Modbus clients to the software, instead of a real Modbus server device, in order to test and configure clients. Using a simple control language you can simulate a Modbus server measuring environment properties (e.g. flow rate), controlling the environment (e.g. opening valves), performing internal calculations (e.g. averages), and responding to Modbus commands from clients.
Modbus, Modbus TCP/IP
Displays the Modbus device registers as they change; Provides a trace of Modbus messages between slave and masters; Online manual/HOWTO/troubleshooting facility; Full support for coils, discrete inputs, input registers and holding registers, using commands 1, 2, 3, 4, 5, 6, 7, 8, 11, 15, 16, 17, 22 and 23; Supports network and serial (RS232/RS422/RS485) interfaces using the Modbus/TCP, RTU and ASCII protocol variants; Cross-platform: runs on any system that supports Java 1.4 or later - including Windows, Linux, Solaris and AIX; All known extensions of the Modbus protocol for handling 32-bit and 64-bit integers and floating-point numbers are supported; Can transfer a mixture of integers and floats, of different sizes, in a single message; Flexible address mapping allows separate or overlaid address spaces (for coils, discrete inputs, input registers, and holding registers) with arbitrary bases; Registers are individually configurable for type (integer or float), size (16/32/64-bit), and radix (binary, octal, decimal, or hex); Supports broadcast requests (slave ID 0); Online example simulations.
For more information, see http://www.wingpath.co.uk/modbus/modslavesim.php