ProSoft Technology MVI56E-MCMR - Manual (Page 191)

MVI56E-MCMR ♦ ControlLogix Platform Reference
Modbus Communication Module with Reduced Data Block User Manual
ProSoft Technology, Inc. Page 191 of 225
May 13, 2014
In this example, the Master addresses a request to server device. The function
code (01) is for a Read Output Status operation. It requests the status of the
output at address 1245 (04A1 hex). Note that only that one output is to be read,
as specified by the number of outputs field (0001).
If the output address is non-existent in the server device, the server will return
the exception response with the exception code shown (02). This specifies an
illegal data address for the Slave.