Author Topic: Modbus server  (Read 1285 times)

MrPike

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Modbus server
« on: April 02, 2019, 02:17:01 PM »
Hi all, I know AHMI is a client only but I was wondering if anyone has found a Modbus library out there that allows for creating your own modbus server application.  I have played with EasyModbus but ran into some walls and the support seems to have fallen off.  I appreciate any info in the right direction, thanks.   

Godra

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Re: Modbus server
« Reply #1 on: April 03, 2019, 09:47:18 PM »
MrPike,

I don't understand what you are trying to do and, since there are no other responses so far, I am not sure if other members understand it either.

AHMI is a client and would normally connect to a Modbus slave device, which should be referred to as a server since it provides all the requested data.
MODRSsim2 program could be considered as a server which interfaces multiple simulated slave devices to the client.

If you are trying to create a slave simulator then maybe take a look at this post:

https://www.advancedhmi.com/forum/index.php?topic=765.msg4720#msg4720

Maybe I got it all wrong all together.

Phrog30

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Re: Modbus server
« Reply #2 on: April 03, 2019, 10:26:20 PM »
I think he's talking about a distributed system, like a tag server. So, if you have 5 AdvancedHMI instances running, you are polling data five times, instead of once from the tag server and the other 4 clients pulling from it. That's how I read it.

MrPike

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Re: Modbus server
« Reply #3 on: April 08, 2019, 07:15:44 PM »
Sorry for the vagueness guys. Yes Godra you read it right. I want to create a application that does what ModRsim does(modbus slave/server) but for a specific device. This will be designed for my sales dept to be able to demonstrate a product and not have to manually change values like ModRsim would require. So far I have been able to crack the code and press forward with a library from EasyModbus. I appreciate any info on other libraries if you know of any. Thanks.

Godra

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Re: Modbus server
« Reply #4 on: April 08, 2019, 10:56:47 PM »
MrPike,

The link in my previous post has solution that uses nModbus libraries for ModbusRTU communication.

You should provide more info about your project and hopefully upload what you've done with EasyModbus libraries (possibly modified so it does not expose any of your company's secrets).

Is your sales dept demonstrating ModbusRTU or ModbusTCP devices?

It sounds like you would just want to be able to specify/change a slave ID in AHMI and have the current controls show that slave's values.
This could possibly be achieved by creating a code within AHMI, depending whether the slave is ModbusRTU or ModbusTCP device.