We want to dump a 'parameters table' used by the program of the slave, for reconfiguration purpose. That requires a new protocol on top of modbus. Is there an off-the-shelf work already done about this?

The slave runs a program (on a C167) designed to work with many different mechanical devices and configurations. For each configuration, a parameters table must be dumped. We are about to create a simple layer on top of modbus (which is NOT a TCP-Modbus) to access, read, write, one or more or all parameters of this table. The master is a PC. There would be about 50 parameters, not subject to change very often. The main issue is to design something expandable and capable of improvment.

My question is: does Modicon has ever developed (or heard of) any standard, existing norm or protocol dealing with such a subject?

 

Look at "www.modbus.org":http://www.modbus.org you will find alot of helpful information there as well as all the know function codes that modbus uses. I believe one of these is for programming/configuration and it may be helpful to you.