Modbus on 5282

[smkraft]

I may need to implement a Modbus/TCP server on a 5282. Has anyone done that who would be willing to share their experiences? In particular:

1) Did you start with the RT automation stuff, code from modbus.org, or something else?
2) How long did the implementation take?
3) Is there anything in particular to look out for?

Thanks,
Steve

[bbracken]

Steve,

1) Did a ModBUS implementation on a MOD5270
2) Did not use the RT automation software, did it from scratch
3) Entire project took 8 weeks - there were additional functions of this project in addition to the ModBUS

ModBUS is pretty straight forward. In essence it is registers that are inputs or outputs. A TCP socket is used to read and write the registers. The project that I worked on did not implement all of the register types nor did it implement the entire register space.

I mentioned to the company that I did the project for if they had considered the RT Automation software? They were pretty adamant about doing their own. Don't know how expensive (royalties) the RT Automation software is, but it might be a good starting point.

Bill Bracken

[bbracken]

Steve,

Micrium also has a ModBus stack.

Bill Bracken

[gavinm]

Hi Bill,

I too am looking at needing to communicate from a Netburner MOD54415 using the ethernet interface to some slave I/O that uses the Modbus TCP protocol. All I need to do is regularly update the state of 8 to 16 digital outputs on the ethernet connected slave.
Are you prepared to share any of your code or any of your recommendations?

[rnixon]

8 weeks is quite expensive if you count your time. I would check with real time to see what it costs.

[dciliske]

Second the comment about Real Time Automation (http://www.rtaautomation.com/). They have significant experience with Netburner products and have protocol stacks that directly integrate with the NNDK.

-Dan

[gavinm]

Ok thanks guys.

As I said, my requirement is VERY simple so I was looking for a "quick and dirty" (ie cheap or free) bit of help!

I've found www.simplymodbus.ca that seems to give the required info, so I'll maybe have a go myself and report back ...