Controllogix, ehternet/ip, communication

I am trying to get data out of a controllogix to a PC. After looking at the ethernet\ip spec, it looks like it is 'data' with
an ethernet/ip/tcp header. no checksum, just ethernet\ip header, then data. If this is the case, would it be possible to send msg from the ethernet module to an open socket. I belive the message would be stripped of the ethernet/ip/tcp stuff and leave me with just the ethernet\ip stuff. I believe that this could be parsed for info.
I haven't tried this yet, but am assembling the hardware/software.
(I know this can be done with a $1500 rslinx but am looking for a cheaper, faster way)
We do have a 3rd party ocx (automationtechic???) that works great but I am looking for an alternate route.
Thanks for any help.
By the way. This controllogix by AB rocks.
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Can do with $ 500 CIMplicity 50 point Plant Addition and assume also with Wonderware and others.

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Thanks for the reply.
Yeah, there are several vendors that provide com to the controllogix. Nothing like DIY for learning though. Since I embarked on the DIY path I've learned a lot about ethernet, IP, TCP and ethernet/ip (including how to spell it). I'm finding all required info on EIP but it seems that the greatest barrier will be how AB implements it. (service id's ect). I've been sniffing with ethereal and am making some headway. This will be harder than coding for DF1.
Again, thanks for reply.
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Made a little bit of progress this week. Using VB6 am able to register session. I hope that by beginning of next week to be able to interrogate tags in the clx. Sweet, AB followed the ethernet/ip standard (up to the CIP where the standard seems to loose direction) and then they (AB) provided the literature to complete the task.
Is AB having a change of heart? Are they becoming OPEN SOURCE?
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Mike: I think you were mistaken when you said "cheaper and faster". It's obvious the faster method would be to use established products. Also, depending on what you make an hour and how many hours this takes you, doing this from scratch might turn out to be more expensive. In that case, you will not achieve either of your goals (cheaper and faster). If this is strictly a learning exercise, then sure do it. But if this is for a quoted project, then you are wasting time and money by reinventing the wheel. If you are looking to compete with these established companies then all I can say is 'good luck'. I hope you come up with something you can sell.
Just my opinion. Since everyones got one, we know what they're worth...
snipped-for-privacy@yahoo.com (Mike) wrote in message

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snipped-for-privacy@yahoo.ca (Andy) wrote in message

Abattler, Thanks for the reply. No, its not a quoted project. Yeah, you're right! I have spent a lot of time on this. But I am learning a lot about TCP/IP as well as Ethernet/IP. So,yeah, its a learning experience (so far). I am making progress. It looks like all of the comm apps for CLX are servers (RsLinx, interchange and other 3rd party vendors that I have tried). I would like to see if getting rid of the server layer would increase throughput. Some time back I was successful at DF1. From that I was able to incorportate PLC5, SLC communication on several operating system as well as several microcontroller apps. I hope that lessons learned about ethernet/ip will be useful as well. Another reason for the exercise, in one application HPUX plays host to the CLX. And Interchange is not making it (previously used PLC250 with the PLC5 file type exchange it was just barely fast enough). So, if I am successful, I will be able to port it the VB to C - HPUX. But you're right I wouldn't want to do this within a time/money budget. Thanks again for the reply
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