MODBUS and ML1400

I am using a ML1400 to communicate via MODBUS RTU with 16 Powerlink G3 controllers. In the manual for the G3 controllers they state that there is another level of MODBUS Data called General Reference which is in the (6x) instead of the typical Coil (0x), Inputs (1x), etc. These controllers have some pretty useful data in this range and I was wondering if there was a way to use the MSG command to manipulate/access this data. The message setup screen does not give any option with (6x) included. I've searched the AB Knowledgebase and haven't been able to find anything refrencing this data range.

Any help would be greatly appreciated.

I think you might have hit the proverbial wall, here: MicroLogix 1400 controllers don't support the Modbus function codes necessary to read and write Extended Reference memory.

The Extended Reference memory type is described in the old Modicon PI-MBUS specification document (it's the one marked 'For Legacy Applications Only'): http://www.modbus.org/specs.php

Ken,

Thanks for the confirmation of what I believed. I was pretty sure that was the case, but was hoping someone with a lot more knowledge about AB than me might know a trick or something that I missed. Fortunately, I can still do what I have to do without the General Reference information...it just would have made for better HMI interaction.

Thanks for taking the time to answer my thread!