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Modbus Serial: When creating new Data Sources, enabling the point doesn't actually enable the point.

  • Greetings, all:

    I emailed about this a while ago-- It's more of a nuisance than a "broken thing", but here's what happens: This is on Mango 3.6.5,. running on ARM

    (1) I verify operation of a New Device using the MODBUS TOOLS in Mango- Polling stuff to make sure it works.
    (2) Then I go through, and configure points. This usually starts with me importing a Template file that has the names and such, and then I go through and use the edit buttons to change the Offset as necessary.
    (3) It used to be that when the little enable slider was set, the system would poll, and off you go.
    Now, it doesn't seem to do that. When I enable the slider, it just sites there saying "No Value"

    Restarting the data source doesn't fix it either. I seem to have to restart Mango in order to get this to work, at which point it comes up fine.

    This Data Source is attached via a Serial to USB adapter. I have (3) devices on this little RS-485 segment. One of them is a power meter, and it always seems to be fine. The other two are inverters. They all work via Modbus Tools, but it seems there's something strange about adding/editing points and then enabling them.

    This is a sort of a pain when I set up net devices, as this behavior seems to exist whenever you turn the thing off and on again.. Ie, if I make a change to a point, and it saves and updates, that point doesn't start polling again.

  • In researching this:

    This may actually have been fixed in the 3.6.5 version-- I was running the previous version on that machine.

    When I tried to update, though, the whole thing came crashing down. So.. Another thread will be created soon on that.


  • I have been doing a lot of Modbus data point work in the last 2 months and have not encountered this before. The point will show no value until the next successful poll on that point then it will show its value.
    What could possibly be happening is that your poll intervals are quite long or you lost connection to the API and are not getting point value updates on the point table.

    Are you perhaps working through the cloud connect proxy? I have noticed when I use the proxy, sometimes I need to switch tabs then go back to the data point tab in order to refresh the values.

  • Greetings:

    So. I've still got this problem, or some variation of it, and I can replicate it at will. This is now happening with many different kinds of Inverters, but not with my power meters or my other input modules. Something is strange in the timing here.

    So: I'm running 3.7.3 on Java8, and am able to successfully poll everything. BUT ONLY AFTER A REBOOT. The Modbus Tools don't work right, or if they do, polling once causes the Modbus driver to lock up with that /dev/usb device I am using. This requires a restart to clear.

    I got this all working, and thought "yay, we're good now". Reboot, comes back up, Mango does 1 or 2 successful polls, then stops polling, and I get the little ! next to the point, and it stops updating. In this case, I was changing some of the point settings (Switching from a UINT16 to a UINT32, and adjusting units for some of the points).

    I'm going to reboot again, and not touch it, and see if it keeps going. I can provide you with remote access or we can do a screen share for this. This is endemic now with my sites, and is sort of irritating to constantly reboot the machine to unstick whatever gets stuck.


  • Okay.

    There is Definitely a Bug in Mango-

    I just upgraded one of my sites from 3.5.x to 3.7.3 and had all of the devices on one of my USB to Serial converters not work.

    This system has (2)- One is talking to inverters, the other is talking to a meter and some other stuff. The "meter and other stuff" one is fine, but the inverter one is most certainly Not Fine.

    So far, I've been unable to get this going.

    This is a USB to Serial converter attached to a Linux box, running on Java 8.

    To stress again: This was working Fine before the upgrade, and I just upgraded it, and it isn't working. Reboot isn't solving the problem this time. I've already upgraded to the latest JSSC.

    What changed in the serial drivers here?