Read I/O via Modbus TCP

Hi!

Could any body show me Modbus frame to read output(s) for reference!
(complete frame or only addressing section)

Example: Read %Q103.5 from first rack, PLC Telemecaniqe TSX 57 473

Thanks in advance

first of all what is your requirement with modbus adressing with Telemecaniqe TSX 57 473(??), becoz. it by default support unitelway.

Whatsoever try installing modbus comm. driver then connect your plc to the application software through modbus. remember to intialize modbus in the communication port of your programming terminal. then you might read any output status through the application software.

regards,

That's interesting... I did not know that Modbus protocol even allows to access the physical outputs memory.

LadderLogic said:

That's interesting... I did not know that Modbus protocol even allows to access the physical outputs memory.

Click to expand...

I think it depends on the controller. It's really up the the manufacturer to decide where address 00000, 30000, etc. is in memory.