My PLM forgets everything every once in a while

[someguy]

I have my house set to go on "vacation" mode when none of our Motion Sensors are tripped for 12 hours. Today, for the third or fourth time, despite us being home, my house goes to "vacation" mode and I realize that my ISY has no idea what is going on in the house. My solution (each time) has been to do a "Restore PLM" and this fixes the problem. It seems as though my PLM is "forgetting" everything. When this first happened about six months ago, I replaced my PLM and it has happened two or three times since I replaced it. I tend to want to blame my ISY for this. Any ideas as to what may be causing this or how I can sort it out?

[LeeG]

The next time it happens do a Show PLM Links Table to see what the actual condition of the PLM is. A corrective action is known (Restore Modem) but what is that action correcting for. I understand the symptom it is addressing, what I am looking for is what actual condition exists. Are all the link records gone or is the PLM only locked up, that type of question.

 

Since there are hundreds if not thousands of ISY/PLMs running today that are not having this symptom I think it is important to determine what the problem actually is.

 

What ISY firmware and what PLM firmware is being used?

[someguy]

The next time it happens do a Show PLM Links Table to see what the actual condition of the PLM is. A corrective action is known (Restore Modem) but what is that action correcting for. I understand the symptom it is addressing, what I am looking for is what actual condition exists. Are all the link records gone or is the PLM only locked up, that type of question.

 

Since there are hundreds if not thousands of ISY/PLMs running today that are not having this symptom I think it is important to determine what the problem actually is.

 

What ISY firmware and what PLM firmware is being used?

 

When this problem happened the other day, I clicked on the "Show PLM links table" and then "start" and nothing happened. no links came up. (and by the way: after I clicked "Restore PLM", a long list of links come up when I do this)

 

ISY firmware:3.3.3

the PLM says v99 when I click "PLM info/status". I just bought it about six months ago, so it is up to date.

 

I appreciate the help.

[LeeG]

Thanks for additional information. Lots of us are running v.99 PLM firmware. I doubt many stayed at 3.3.3, 3.3.7 (RC4) was just announced.

 

If I might suggest the next time running Tools | Diagnostics | Event Viewer at LEVEL 3, then invoke the Show PLM Links Table. Cannot tell for sure if the PLM link database is empty or just failed to respond to the PLM Get Next request. If the PLM did not respond to the Get Next response it may only need a power cycle rather than a full restore. The Event Trace should show how the PLM reacted.

[someguy]

Thanks for additional information. Lots of us are running v.99 PLM firmware. I doubt many stayed at 3.3.3, 3.3.7 (RC4) was just announced.

 

If I might suggest the next time running Tools | Diagnostics | Event Viewer at LEVEL 3, then invoke the Show PLM Links Table. Cannot tell for sure if the PLM link database is empty or just failed to respond to the PLM Get Next request. If the PLM did not respond to the Get Next response it may only need a power cycle rather than a full restore. The Event Trace should show how the PLM reacted.

 

Okay, thank you. I'll try that. It could be a week or a few months, but I suspect that it'll happen again.

[someguy]

Okay, it happened again today and I set the event viewer to level 3 and ended up pressing "start" for the "PLM Links Table" three times and here is what it showed:

 

 

 

I'll try power cycling the PLM now and see if that fixes it.

 

also: Yesterday I upgraded to 3.3.7 (RC4)...whatever RC4 means...

[LeeG]

The 02 69 command is a request for the first link record in the PLM. The 15 response either means there are no link records or the PLM does not like the 02 69 command. Since the 02 69 is the correct command it looks like the PLM has no link records. It could also mean the PLM is hung up with the last command and will not accept a new command.

 

It will be interesting to see if the PLM works correctly after a power cycle without actually doing a Restore.

 

The RC stands for Release Candidate. If the image is stable (no major bugs) it will become the next Official release.

[someguy]

The 02 69 command is a request for the first link record in the PLM. The 15 response either means there are no link records or the PLM does not like the 02 69 command. Since the 02 69 is the correct command it looks like the PLM has no link records. It could also mean the PLM is hung up with the last command and will not accept a new command.

 

It will be interesting to see if the PLM works correctly after a power cycle without actually doing a Restore.

 

The RC stands for Release Candidate. If the image is stable (no major bugs) it will become the next Official release.

 

Power cycling the PLM didn't change anything.

 

FYI: power cycling the ISY didn't change anything, either.

 

I had to "restore PLM" again to resolve the issue today.

[LeeG]

Thanks for that additional information. That sure makes it look like the PLM lost the link database. Difficult to see how that is happening on multiple PLMs. The ISY would have to issue a Serial command to reset the PLM. Conceptually possible but that would be so obvious to anyone using an ISY as all Scenes would stop working and all device driven Programs would no longer function.

 

Is there any other application involved that could communicate with the PLM over the powerline? It would have to be over the powerline as nothing else has access to the Serial interface unless the PLM is shared with another application.

[someguy]

Thanks for that additional information. That sure makes it look like the PLM lost the link database. Difficult to see how that is happening on multiple PLMs. The ISY would have to issue a Serial command to reset the PLM. Conceptually possible but that would be so obvious to anyone using an ISY as all Scenes would stop working and all device driven Programs would no longer function.

 

Is there any other application involved that could communicate with the PLM over the powerline? It would have to be over the powerline as nothing else has access to the Serial interface unless the PLM is shared with another application.

 

I don't think anything else communicates with the PLM. I'm really don't know what could do that. I use some REST commands from my REDEYE remote control system to control the ISY, but this doesn't sound like what you are asking.

 

Any suggestions as to how to resolve this problem?

[LeeG]

I tried various REST calls without success. The PLM is not in the nodes list but I tried using the PLM address anyway. The REST call fails. I was thinking there might be another application involved that interacted with the powerline that could reach the PLM that way. There are few other REST calls I want to try that are not node specific. I have a very old 2412SH PLM that came with one of the first HouseLinc Desktop releases many years ago. It routinely loses its link database so I know it does happen but this thing is ancient. It still functions as a good powerline interface so I keep it around for test purposes. I’ll continue to look for some way to explain the behavior but at this point I don’t have any good theories. Seems odd that two PLMs would have the same issue. Just as odd that the ISY would be responsible as this would affect anyone running an ISY. That’s why I was looking outside the normal environment.

[ELA]

Merry Christmas Someguy,

 

The PLM stores its link records in what is called an EEprom. Depending upon how well they are designed into a device they have been known to get corrupted.

 

Any chance you experience brief power outages from time to time? One way in which that type of memory can become corrupted is during a brief power outage.

Not real common but possible depending upon the timing of the power outage.

 

Another possibility is a loose connection between the serial daughterbrd and the main PCA. The EEprom is located on the daughterbrd and if the connections between brds becomes loose that could also corrupt the links memory.

I tended to exclude this possibility based on the fact that you have experienced this on two different PLMS.

 

Any chance you have the old PLM or a spare?

 

I would like to ask LeeG to comment here if he thinks this would be worthwhile or not?

 

With a spare PLM as the interface you could use Simplehomenet Suite to read the link records of your suspect PLM. If you then viewed the raw serial data you might be able to determine if the first link record location has been totally zeroed out ( as in a factory reset) or if just the first byte might be corrupted, for some other reason. Ideally you would read other locations beyond the first as well but I do not know if SHN utility will allow that. That can be done using a terminal program.

[LeeG]

ELA/someguy

 

That will work. The Simplehomenet Utility Suite (free download from SHN web site) has the capability to read specific link records by number. Number 1 would be the first link record, Number 2 would be the second link record, etc. All zeros in slot 1 and 2 would suggest a PLM that has been factory reset. Actual data in some of the locations would need evaluation to see if it looks like the remains of a valid link record that has been corrupted. The ISY does not directly address any link record in the PLM. It gives the PLM a link record and directs the PLM to update the existing record or add a new one if not found.

 

Besides other users not seeing this, the fact that the ISY updates existing link records is another reason it is hard to see how the ISY would be the cause. Even deleting a PLM link record is a logical request to the PLM through the Serial interface. The ISY has no direct contact with the link records themselves in a PLM. All physical link record access is done by PLM firmware/hardware.

[someguy]

This happened again a couple of days ago and then again today. Getting old. I think I'll just buy ANOTHER new PLM. I don't really have time to goof with this simplehomenet solution.