Where can one find the modbus addresses for AC890?
Are you talking about Modbus/RTU via the RS485 option card or the Ethernet card and so Modbus/TCP? There is a difference in terms of how the Modbus mapping is set up, though the general answer is it depends on how you map your data, there isn't a 'fixed' mapping per se.
For Modbus/TCP, the Ethernet block (which you add to your DSELite project) - under the Block -> 890 Comms menu) is where the 'mapping' is done.
First you add the individual Value Inputs or Value Outputs available under the BLock -> 890 Comms menu to your project, tying them to whatever input or output values in the configuration you want to exchange via Modbus.
Then when you go into the EN block (ethernet block) and configure for Modbus, you add Inputs or Outputs and point those individually to the Value Input and Value Outputs you've already added in your configuration.
The details of this are available in the particular option user guide. The Modbus/RTU uses a different block than the Ethernet (EN) block but similar type of concept. The particular option user guide you need is available from the 890 product page. Link here:
From this user guide, this page shows the address offsets for Input versus Output data and how many registers are supported if you add that many to your project. Also shows the function codes supported. Modbus/RTU will be slightly different, but again, the details are in the RS485 option user guide.
Rough example of Modbus/TCP project shown below. The 'addresses' shown are more for reference as the actual Input or Output name is arbitrary.
Thanks fo the reply. I thought the modbus addresses would be they were the same for the different busses. Good to know.
From looking thru legacy code, I am communicating over RS485 and see
0/1 is speed command
2/3 is pos torq
4/5 is neg torq
Here is the link to the RS485 COMMS option user guide.
Specifically, see page 12.