ML1100 - using MSG command to send data to a PC?

[schaya]

Unconventional I assume, but wondering if this works. If i built a listener in some other language and set the multi-hop ip to that of the PC, would it work? If so how would i need to configure the MSG command?

thanks!

 

[Gil47]

I don't really understand your question but will make a sugestion .
The ML1100 has a Web Server built in, which can be configured to display data, then from a PC Web Browser, you can read the Web Server in your ML1100 via the Ethernet connection.

Would this give you what you are after.?
Please expand on your question.

 

[schaya]

i do know about the embedded webserver, but its not quite what im after.

I was thinking along the lines of sending data from the PLC to a listening service/application on a PC (think like an EVENT, item passes scanner, values for something drop below range, etc)

Kind of the same information youd be passing from one PLC to another, just with the destination of a PC instead of another PLC

like i said, slightly unconventional. but does it make sense?

 

[Ken Roach]

The way that's generally done is to make the listening application on the PC an OPC Server with "unsolicited" messaging capability (RSLinx Classic does this) so the PC application can just use ordinary OPC connectivity and wait for the data to arrive.

I've had some customers who don't want to use OPC, but just want to "open a socket and receive some data". Shortly thereafter they want to detect the sending data types, then they add error checking, and retries, and.... pretty soon they've written a device-specific driver instead of using a universal software interface.

MicroLogix does not have the ability to generate a generic TCP socket connection; it ONLY does ODVA-defined EtherNet/IP messaging. ControlLogix has some additional capability for generic sockets using the 1756-EWEB and 1768-EWEB modules.

 

[schaya]

Ken,

appreciate your reply. Funny thing is though, a device specific driver is more or less exactly what im going for. I did some experimenting with wireshark and a simple plc program set to send out a string every 15 seconds, and i can definitely see something attempting to come across, but something is not right. Could be how i have the MSG block setup, could be the format of the packet, etc.

So say i did want to ignore the ease of using OPC and "open a socket and receive some data", what would be the best way for me to go about this.

thanks again for your reply!

 

[Ken Roach]

This is me going on record: It will be faster and cheaper to buy an unsolicited OPC server that supports the PCCC command set over EtherNet/IP.

But if you're gung-ho, the best document for you is "Communicating with Rockwell Automation Products using EtherNet/IP Explicit Messaging".

http://www.rockwellautomation.com/enabled/guides.html

If you intend to sell your software commercially, you will have to join the ODVA and subject your software to a conformance test.

 

[bkottaras]

Welcome back Ken!!

 

[schaya]

Ken,

thanks, i appreciate your help.

 

[joshd]

ASCII message with a socket connection

Hi schaya,
I believe we've already done exactly what you are looking to do. Have a PC communicate with MSG Commands to send and receive data with the PLC but not use OPC or RSLinx.

We have a communication product to communicate to a variety of shop floor devices and this type of functionality was added awhile back to send ASCII data back and forth to an AB SLC 5/05 over Ethernet.

We wanted to avoid the overhead and limitations of OPC and/or RSLinx.

I stumbled across this post while looking for something else. Not sure where you are at with your project, but if this is something you are interested in just let me know.