Trouble with Serial Comms to an Alarm Panel

Vera Controllers, Services & Devices General Vera Discussions
#1

Hi all

I need some help. Much hair pulling out here.

I’ve got a Texecom Alarm Panel plugin communicating with Vera Edge over Serial. Every now and then they stop communicating.

I’ve done much debugging and logging and this is what I can be sure of;

  1. Luup.io.is_connected() returns TRUE, so I know the interface is connected
  2. Luup.io.write() returns TRUE so I know that my data was sent
    … but when the comms fail, nothing comes back.

You might think its because the Alarm panel is stuck, or non-responsive… yep, I thought that too… but here’s the odd thing… a Luup.reload ALWAYS fixes the problem (for a few hours). Why would reloading the Luup device make the Alarm Panel start communicating again? Surely the issue must be in the vera buffers or something…

I’d love to do a Luup.io.close() and luau.io.open() again when they stop communicating, but these calls don’t exist… so how do you “reboot” the serial connection without reloading the entire Luup several times a day ?

thanks for any help…

#2

Without being familiar with your panel it appears that you are dropping signal between the panel and Vera.

A couple of simple suggestions. Ensure your connections at both ends are well secured. A loose serial connection can cause signal dropout.

Another well known cause in the serial world is poor cable chipsets. Plenty of cheap Chinese “knock offs” which are known to cause comms issues too. The FTDI chipset are probably the most reliable assuming they are genuine so I’d look at replacing your current cable as the cheapest first stop for troubleshooting.

I’m assuming all your serial port settings are correct in your Vera setup.

#3

Hi Peter… thanks for your thoughts.
I don’t think this is a hardware problem. I have the RFXtrx on the same serial channel via a USB Hub and that behaves impeccably. Also, that wouldn’t explain why EVERY time, a Luup reload fixes the issue for a few hours.
I also tried to use COMIP so I communicate over LAN instead of USB (though both still hit the alarm panel over serial)… and the problem is the same.

I’m currently looking into memory leaks using free -h and df -h…

Its a shame that the comms library doesn’t allow an individual Open/Write/Close cycle per poll, rather than the port opening on startup and never closing, since I can’t control the way the lower levels of the interface work…

Any more thoughts appreciated.

#4

One last thing I’d try on the hardware side is to remove your 4 port hub from the equation and connect your Texecom panel directly to the VE and leave it running for 24 hours and see what results it yields.

I assume your 4 port hub is powered.