Modbus RS485入门

Question

I am not sure if this is the right place for this, however if it is do let em know will post it there. My issue is
I need to read infos from

Moxa 5430 RS485 to Ethernet converter (Hardware)

Using Modbus RS485 protocol. Its a electricity department , as I am new to this protocol I am not sure how to start getting reading from this device , I have googled and downloads few codes but it none satisfies my needs.
If there is any tutorials where I can go through specially if its for electric meter reading that would be even great.
They get their reading on notepad so I am guessing they already have some application installed, but due to security reason cannot access that PC. So any help would be great I am using C# and SQL 2012 as the platforms.

Thanks

Answer 1

Ok. Now Moxa 5430 is a terminal server device capable of translating 4 RS485/422 physical into 4 tcp channels you can use remotely via Ethernet. The configuration for the device in terms of server/client has to be in the device manual. Essentially, you have to configure the device as a server and allocate a port for each RS485/422 port you have. Modbus is a communication protocol designed to interface with a huge plethora of PLCs and was created in 1979. More information on Wikipedia http://en.wikipedia.org/wiki/Modbus about this protocol. I personally recommend reading a little bit about the modbus protocol before adventuring in using it. So with these two out of the way you can use a library like the following https://code.google.com/p/nmodbus/ which can help you communicate with Modbus devices via serial channel or tcp/ip. However you will need the details about the real modbus device you are connecting to (power meter ,PLC, etc) and the supported command set of that device). The moxa device is just a convertor from serial to ethernet.