Posted by angelino on 2015-10-28 09:41

Ah Ah yes this I have done allready, sourceforge also !

I could find only modbus RTU which is not modbus tcp, there is a modbus tcp like example on github but it is commented in chineese.So this is reason why I am asking the people here.Because I hope someone allready ported or developped a modbus tcp or a modbus tcp running on lwIP or native stm32f4 API code (like bare metal c code)

So yes I went on github and doing the proprer research would give -> Github

Then this unique modbus tcp port is based on uIP which is just another lightweight ethernet stack but not lwIP stack
So it looks like you have read my request too fast.

Thank you though for your help

Posted by bugmenot on 2015-10-28 15:24

> So it looks like you have read my request too fast.

Maybe, sorry.

> Then this unique modbus tcp port is based on uIP which is just another lightweight ethernet stack but not lwIP stack

In case if nobody comes forward with lwIP port of FreeModbus, I think you shouldn’t be too fast to dismiss this Chinese example. The whole “port” is in this directory, it’s just a couple of hundreds lines of code. It must be relatively easy to change the uIP functions with the lwIP functoins and you will have your lwIP port of FreeModbus. Or at least it might give you the idea how to create your own port. It’s straightforward, you must implement some callback functions of the transport layer.

Posted by angelino on 2015-11-03 15:53

Hi bugmenot,

>> So it looks like you have read my request too fast.

>Maybe, sorry.

Talking of which I read back my answer and it could seem a bit agressive, well I was not trying to be rude in any way, so if you got it that way, it was not on purpose and I am sorry about it.

So first of all thank your for the answer.

Well you maybe right I will try to port it myself, the main problem for me is that when it comes to device driver, I am confident with device drivers writting but I really don’t get everything about the ethernet stack, so I basically hoped to get a modbus tcp driver sample to understand how it works with the stack and not really understand how it works and how to port it in order to port my own.

But it seems that I won’t really have the choice here so ...

The thing is I don’t really know where to start from, in order to focus on modbus port, because lwIP stack documentation is huge.

I guess I will have a closer look at modbus tcp port for uIP and lwIp documentation.

Thank you though for your time