Flex727

Yes, my understanding of how the database number matches up with firmware version is likely incomplete. I haven't been able to obtain or create a table of firmware vs. VisiLogic version, but I think that would be useful. Regarding not being able to open your 9.8.31 saved program in 9.8.9, this is true but be aware that VisiLogic saves a backup of the original file when it opens the file in the newer version. You'll find it with the file extension changed from .vlp to the database number.

VisiLogic 9.8.65 has the ability to zoom in on any PLC screen, even the V1210.

That's usually where I place my bet.

Check out the example projects for the recommended way to execute MODBUS commands.

Reset means re-boot and is equivalent to a power cycle. Re-initialize means reset plus erase all memory operands. Either can be performed from the PLC INFO Mode or from the VisiLogic Connection menu item. It's usually a good idea to re-initialize prior to (or immediately after) downloading a new program for the first time.

Those questions were important. A third question: is your ladder in a subroutine? If so, is the subroutine being called in the Main Routine? If the answers are all "yes", then post your .vlp file here for additional help.

@Marko, did you try having VisiLogic re-install the USB driver? Also, try using a different USB cable. Any USB-to-mini-USB will work.

I just tried it again in 9.8.65 and realize now that I failed to select COM 2 in the INIT block. COM 1 can only select RS232, COMs 2 & 3 can select either.

Are you 100% sure power flow is passing through the compare block, MB 10, & MB 12? Is your MODBUS block actually writing to the slave? I use the V700 frequently. There is no issue with the Store Direct function that I've seen.

Unfortunately, no.

With all display issues I make sure the firmware on the PLC is up to date, then download a BLANK project, re-initialize, then download my working project. If you still have a problem, you will need to contact your distributor or Unitronics for any other available remedy.

@swb311, the V700 PLC has a different ethernet module than the other Vision PLCs. Because of that, some of the system operands are not valid. Instead, there are ladder functions available to replace those system operands. As Simon mentioned, this all very well documented in the Help file.

Have you checked out the example projects that come with your VisiLogic installation? Look for the file called "V700_Modbus_TCP_master.vlp".

I checked this out in 9.8.65 and the problem seems real and still exists in this newest version.

Thanks for reporting back your findings!

My understanding may be a bit incomplete, but here is my experience on this subject: When you opened the 9.8.9 project in VisiLogic 9.8.31. you should have gotten a warning message that the project was last saved using 9.8.9 and database 150. VisiLogic 9.8.31 uses database 152. This will mean that the PLC firmware will need to be updated if you want to download the project into the PLC using 9.8.31. VisiLogic will warn you about this and will not allow you to proceed until the PLC is updated. If you do all this the likelihood of having a problem is very low, but I rarely do. Every programmer has his or her own philosophy on this. Mine is that if the PLC is working well at an installation, I do not update the firmware unless there is some specific need for it. I keep all the older versions of VisiLogic on my computer and use Version Swapper to select the version used on that particular PLC, make the program updates, and download. Other programmers like to update everything to the latest software and firmware versions whenever possible. Also, if there are multiple Unitronics PLCs in service at a particular location, I try to keep the firmware version the same on all of them for consistency - another reason, in my mind, not to update. So, to sum up, I would download 9.8.9 and use it in your situation. Other programmers might do it differently. I don't think there is a definitive right or wrong here. Obviously, if you can't get Version Swapper working it leaves you little choice. However, I will say that I've never had a single issue with Version swapper. Two things to remember about Version Swapper: 1) Always use the version of Version Swapper that was installed with the latest version of VisiLogic, and 2) As with all Unitronics software, be sure to install and run "As Administrator".

This is fascinating. I'm learning some things about the differences between expansion I/O modules and Snap-In I/O modules that I haven't thought much about in the past. My thinking is that there is a more "intimate" connection between Snap_in modules and the PLC than expansion modules. There are 8 pins (lines of communication) between expansion modules and the PLC, while there are 34 pins connecting the Snap-In module to the PLC (they may not all be used and at least 2 or 3 are used for power & ground). This would seem to allow for certain additional capabilities that Unitronics takes advantage of. Clearly one of them is the ability to interact with the HSC in real time that can't be done with the expansion module. Any of this sound right?

Ausman is correct (as usual). Only the Master can Read & Write. The Slave merely listens for requests from the Master and allows the registers to be Preset (written) or Read. The Slave cannot initiate action (at least directly).

@Cara Bereck Levy, this issue might need to be addressed in more detail in the help file. If there is a difference between Snap-In and expansion modules in how the HSC behaves, the customer needs to know for proper hardware selection.

You need to provide a LOT more information before someone can attempt to help you. What PLC? Which I/O module(s)? Is the Run command given via a Digital Output from the PLC I/O or some other communication? Has this been a problem all along or is it new? If this has been happening all along, it sounds like a logic error by the original programmer. If so, it may be a simple fix. Do you have the PLC program .vlp file? If so, attach it and someone should be able to give it a look over.

I've never had that happen, but if you've fully removed and re-installed VisiLogic and the problem persists, it sounds like a problem with your PC.

Thank you for that!

Also, I thought the Immediate Reset HSC should work, but I can't find any Help entry on that. This is not a function I've used recently. If you don't get any other help here, just send your question to Unitronics Support. They'll get back to you pretty quickly.

Sorry, replied without thinking. You need to configure a hardware reset. One specific digital input can act as a reset - see the help file. Another thought is to use an ML or DW to avoid overflow.

Does Reset Numeric or Store Direct 0 into the MI not work?