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UniStream & UniLogic Beta
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Everything posted by Damian

  1. Yes, of course. Just an ADD block where one of the Source and the Destination are the same address. You can't read before and after on the same ML. You need to define one as the previous value and one as the current value. Every time you read you need to then shoft the current value into your previous value. To me it would be the other way around. It would be taking the current value minus the previous value to determine the gross of the last fill. That depends on if you need to keep track of every transaction. I might be a bit unclear about exactly what you want. Is it OK to post the program so we can see what you are doing?
  2. It is generally understood no matter whose platform you use that the transitions are based off WHEN in the program that bit of memory gets written resulting in a change of state. It is not (should not be) be directly related to the "housekeeping" portion of the scan. However, if you are reading physical Inputs, then those are updated only during the "housekeeping" portion of the scan. Unless of course you use an immediate IO read to sample the hardware IO before the "housekeeping". Since MB bits are internal, there is no housekeeping necessary for them, therefore the end of the scan is irrelevant. In addition, if you have conditionally executed subroutines in a PLC (which should normally be avoided for a host of reasons) your code may completely miss transitions that came and went because the transitional instruction you are using will base that off of the evaluation of that instruction the previous time it was exectued. On the flip side, you could have the same bit (MB) of memory trigger positive and negative transitions multiple times in one single scan.
  3. You have X1 and Y1 swapped in your linearize function.
  4. Also, it doesn't appear to be application specific because this application opens just fine elsewhere.
  5. Aha, it happended again! Argh!!!!!!!!!!!!! Oddly enough I did not even remember this thread. I did a search for the error on the fourm and up popped one hit. I said hey, look, someone else already had the same problem. Then I said hey, that someone else was me. Getting old is so much fun. Anyhow, the application I was trying to open was in post #8 here http://forum.unitronics.com/index.php?/topic/1501-high-speed-counter/
  6. I don't know anything about ACCESS, but in excel when you import things you have a lot of options and controls over how things are imported and what settings to use. I would expect ACCESS to have these same options somewhere albeit hidden. Not really an answer but maybe a hint at where to look for one.
  7. I think that is exactly his point. Since download is obviously a non-reversable process, why does it show up as an option under the UNDO? Try it yourself. Do a download and then select the download in the UNDO list. If you go back to the undo list it shows that it processed the UNDO? But what did it actually do? It shouldn't do anything. It shouldn't even show up on the list in the first place.
  8. Can we please get a functional chart of the PID process along with the equations involved so that we can better understand what is happening behind the scenes. ALL other PLC/Motion Control manufacturers publish this information so that a clear understanding of the structure can be had. The auto tune feature rarely provides satisfactory operation and there was no means given to favor steady state response or step response depending on the needs of the application.
  9. Why not simply make it a String Entry field? You can also hide a string entry field on some other config screen that allows them to enter the string. That string will point to a location in your string library. Then your text field would also point to that same spot in the string library.
  10. RMozes, Thanks, I already restored my VM to a previous point and it is OK now. Next time I re-install I'll delete the directories you mention. D
  11. So, Visilogic V9.4 crached on me last week. Apparently it crashed very hard because after that I could no longer successfully download from that point forward. Rather than battle this one out, I decided it would be easier to simply uninstall and re-install the software. So I did. At least I though I did?!? After the uninstall process I rebooted. Then I re-installed the software. Then I ran the software. And to my suprise, the very first thing it tells me is that Visilogic was not shut down properly last time and that it would perform the recovery. Really? How could it have not shut down properly last time, when it had never even ran before? And ....... it still opended up my last project from before. How could it have remembered this if it had uninstalled completely? Anyhow, after what I thought was a true re-install it continues to give me the same error on downloads. I installed the software in another VM clone, with everything else being identical. It works in that clone. What do I have to do to make certain of a complete uninstall?
  12. Is it possible for you to normalize these values prior to the PLC operating on them? What I mean by that is 12000 radians is the same as 5.3992485942. (12000/(2PI) - INT(12000/(2PI))) * 2PI If you take the COS of 5.3992485942 in the Unitronics PLC you will get 0.6341115. Unfortunately I tried to normalize the value in the PLC first prior to putting in the COS function but the precision of the FLOAT operation required to do this are just as bad. If someone can figure out how to normalize your values in the PLC without loosing precision then you should be good.
  13. Just a quick tip for all that go back and forth between an extended monitor. First select your program with Alt+Tab so it is the actice application (skip this if it is already active) and then use Alt+Space+M. Now you can use the arrow keys to move the window back into view.
  14. I just realized i had not read the orignal post very well. All of your slaves are V570s as well. I understand where linxchas is coming from now although the solution is definitely specific to using all Vision controllers as slaves.
  15. What 3rd party Ethernet based controllers have you used that support Modbus over UDP? I have never seen any that don't require TCP and the socket dance.
  16. I would recommend using 3 sockets total for the Modbus TCPIP and communicating to 5 slaves on each socket. Make a sequencer to Connect Socket Write a block of holding registers Wait for Write comple Read a block of holding registers Wait for Read complete Close Socket Index pointers to next Slave and repeat Wit a V570 expect about a 120ms access cycle per slave for each socket. Therefore your total cycle will probably be around 600ms using three sockets. If you can live with up to 2 seconds, by all means simplify your code and put them all on one socket. With 15 slaves you will probably be just shy of 2 seconds if you avoid artificial time delays. The above suggestions also assume you both send and recieve your data all in one contiguous block of data. If you have to perform multiple read and writes per every socket connect instance then your times will suffer.
  17. There is one other small trick that might help give you a little better resoution, but ultimately your scan time is going to limit you. Look at Utils > Debug > Interval > You will find a block for Interval Start and Interval End. They give a very precise meaurement of time between two events.
  18. Sounds more like a browser issue. Are you using Internet Explorer?
  19. Also, check your windows "themes". If you stray from the default windows themes it can cause some items in visilogic to display incorrectly or not at all.
  20. I wonder if the auto-zero function is actually causing the drift. I would be curious to see you perform the same experiment without it. This would at least rule out your load cell, which is very unlikely to be the cause of the issue anyhow. I have no idea what the algorithm for the zero-tracking function looks like under the hood. But I would expect that it relies on the peaks and valleys you would get from cyclical readings to determine the hypothetical zero point. So having this feature enabled in a static situation might confuse it. And that might be exacerbated if you have any filtering / rounding activated as well. One of the biggest challenges load cell amp designers struggle with is temperature stability of the electronics. Many recommend that the load cell amp is powered up and runnning a while to stabilize in temperature prior to taking readings. I also notice that in the examples, the zero-tracking function is interlocked with the "LC function is progress" bits. Did you do this as well? Also, are you you executing this function with a one-shot, or do you have it executing every scan? I could see where executing it every scan would also have the effect you are experiencing. Here is some verbage in the HELP on the zero-tracking. Auto Zero Tracking When activated, Auto-Zero Tracking zeros the gross weight according to the conditions you set, enabling the module to automatically compensate for small variations at the zero point, such as those caused by a buildup of litter on the scale platform, or by temperature fluctuations near the scale. Before Auto-zero Tracking can zero the scale: The Motion Band FB must be included in the application. The Motion Band must be active. The In-Motion bit, Bit 0 of the MI linked to LC Hardware Status Messages in Hardware Configuration, must already have turned OFF, indicating that the scale is steady. Once these conditions have been met, Auto-zero zeros the gross weight. Notes ♦ Once Auto-Zero tracking is activated, it stays active until the function is suspended by the application. ♦ Auto zero tracking will not function in uV/V representation mode.
  21. I have had similar issues when the OS I was using did not match up with the version of Visilogic I was using.
  22. Just to put some numbers to this to give the OP a sense of timing. Using a V570 (fastest CPU) and dedicating connections to a single slave each, I can perform a full read and write cycle to 4 slaves in on average 15ms. That is, I can read and write to all four slaves in under 12.5 to 20ms. It peaks out at 20ms and occasionally I might get one 22.5ms cycle hear or there. Not deterministic of course. Now as an example, and I decide to multiplex one socket and talk to all four slaves that way you will find that it takes about 100ms to establish the connection. And this is for each slave. Once you are connected you will want to do a read and a write before opening the socket again. Between that and the socket close that adds about another 15ms of overhead. So all together you will end up around 450ms for a read write cycle to all slaves by multiplexing. So multiplexing in this example is slower by a factor of about 20 times! So, be careful doing it that way. Most of my processess cannot handle that degree of latency. They have developed FAST socket Open/Close FBs that are much faster, but they have not officially released them yet. It is also possible to create a socket pinwheel, although the code gets quite complex. The theory behind it is you use three sockets or so. While you are talking to slave 1 with Socket 1, you start connecting to Slave 2 with Socket 2, then maybe slave 3 with socket 3, once Slave 1 is finished Socket 1 closes with Slave 1 and then connects with Slave 4 while you're still reading from Slave 2 on the other socket. Then Socket 2 closes and connects to slave 5. Etc. You get the picture. It helps mitigate the time wasted establishing the connection.
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