How to modify register values in a PLC via Terminal in Mac OSX?

Simply speaking, I have a Programmable Logic Controller connected to my Mac via a USB to Serial adapter. There is a开发者_高级运维nother adapter converting the RS-232 from the computer to the RS-485 required by the PLC. I would like to simply modify the register values in my PLC via my Mac's Terminal application. How would I go about doing this?

Thanks,

Sam

If it is an ASCII based protocol which you know (at very detailed low level), then you can do it. MODBUS ASCII is one example. Otherwise you should search if there exists an application which is made for testing devices with such protocol. MODPOLL is one example, and it can test MODBUS ASCII, RTU and TCP servers.

If you are a software developer then you could search for a communication library for that protocol and write the test application your self.