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EWeb throughput

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We had a lot of crash problems with an web card and tracked the problem to using Java with it.

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Hmm... Care to elaborate? Are you talking about using Java script on the Eweb itself, or using Java externally to get the dataview/asp information.

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XML parsing in the default libraries in Java is known to suck...as in SLOW. Are you attempting to parse the packet at all or just reading the data and pitching it? (testing the communication interface, NOT the Java library) That is the #1 reason why in the ECMAScript world, most people are adapting JSON over XML.

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We were using Java on the Eweb itself and were having slow uploads and lots of crashes for no reason. We set it up now with open office and have not had a crash since. Also we set it to auto update every 30 seconds to avoid bogging things down if no one is watching it.

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You set it up with Open office? Care to elaborate, I am unfamiliar with this. To answer the other question about parsing XML, I am essentially just reading the data and pitching it at this point. When I use the dataview or ASP I do some parsing, but not with an XML parsing tool. I find XML Parsers are overkill for simple, well defined structures.

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I may have been wrong, looks like we used Microsoft Front Page and wrote it in HTML and it has worked since. We are not sending the data through to any type of operator station or inputs, just a web page so the owner can see how his plant is running.

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Howdy, I realize that it's an old topic and this is my first post as a new guy to the forum, but I was hoping that I was not the first person to ever try this and somebody may have some ideas... I am trying to figure out how to do a DataTableRead on a large INT Array using an ASP CIPMessage instruction on the EWEB. On page 95 in the ENET-UM527E manual, it states that you can use this instruction to do a GET_ATTRIBUTE_ALL to retrieve the information about the device in slot 1 of the local chassis. <% CIPMessage("1,1", 1, 1, 1, 0, 0,"","STRING"); %>. I got this to work. Great. I would like to use a similar CIPMessage (like <% CIPMessage("1,5", 4C, ?, ?, ?, ?,"","STRING"); %> to do a DataTableRead to an array tag named Dint (the tag is Dint[10]). This is only the tag that I am testing with, I used it because of the example that was given earlier in the thread. The actual array that I am hoping to access is much larger. I understand that I may have to do several reads to get all the data, since if I recall the max for a DataTableRead is 500 bytes. So I tried: [xxx://136.129.50.241/rokform/CIPMessage?path=1,5&type=STRING&complexIOI=4C 03 91 04 44 69 6E 74&data=0a 00. It works. Where: 136.129.50.241 - EWEB card 1,5 - my processor is in slot 5 4C - data table read 03 - 3 words in the rest of the command 91 - symbolic segment follows 04 - 4 bytes in the name 44 69 6E 74 - Hex representation of Dint 00 - Optional - padding byte It refreshes the web page and returns the hex string to the web page, but that doesn't do me any good since I cannot figure out how to use/manipulate the data. A bunch of hex on the screen doesn't do me any good. I then modified this instruction to a <form> format and was able to get this to return the same string. <form name="myform" action="/rokform/CIPMessage?"> <input type="hidden" name="path" value="1,5"/> <input type="hidden" name="type" value="STRING"/> <input type="hidden" name="complexIOI" value="4C 03 91 04 44 69 6E 74"/> <input type="hidden" name="data" value="0a 00"/> <input type="submit" value="Submit Button" /> </form> Once again, this works but I don't know how to get the data into a variable where I can work with it. Maybe if I was a JAVA programmer I would know what to do next, but I'm more of a ladder guy... I would like to use something like this: <% CIPMessage("1,5", 4C, ?, ?, ?, ?,"","STRING"); %> I would think that if I put the data from above in the correct spots here I could load in the array as a variable then use javascripts to manipulate the data. Problem is I have no idea what to put where, nor do I know if what I am asking is feasible. I have looked through lots of documentation, including the Logix5000 Data Access manual and I cannot figure out how to package this request correctly. I have also tried almost every combination of putting the complexIOI string into this command and again it just never works. Most of the time the card returns an "ERR: Targer returned general error code 0x05, abject error code 0x00". I have been using the EWEB card succesfully for a few years now, with a page that I designed using the toolkit. I just purchased another EWEB so that I could test with it in hopes of becoming more proficent and posting some cycle result historical data I already have stored in the PLC in arrays on some new pages. I just cannnot figure out how to get "chunks" of array-tag data to the page as a variable that I can "Parse" though with Javascript. I have spent more hours than I care to admit pursing this, and any help would be greatly appreciated.

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