For instance, ABB AC500 series include MODBUS RTU as a default. You need to set up your serial ports (in Hardware Browser) and your Modbus master needs to use COM_MOD_MAST Function Block. If you need it, I can try to get ABB's application note.
You can also test your Modbus RTU Master with this open source tool:
Dear All
Can any one help me in getting the MODBUS RTU library available to communcate on RS485 please.
Hi!
First of all you must specify some things:
1) Which PLC are you using?
2) Are you using your PLC as a master or slave?
3) Which devices are you planning to communicate?
Please have a look at these documents:
http://www.modbus.org/specs.php
http://library.abb.com/global/scot/scot ... 2M0102.PDF
For instance, ABB AC500 series include MODBUS RTU as a default. You need to set up your serial ports (in Hardware Browser) and your Modbus master needs to use COM_MOD_MAST Function Block. If you need it, I can try to get ABB's application note.
You can also test your Modbus RTU Master with this open source tool:
http://qmodbus.sourceforge.net/
Good Luck!