More than 1 ISY talking to a single PLM

[Mustang65]

Well, now that I have a 2nd ISY and I am planning on setting one up primarily to talk to the GEM/DataBox/some Insteon and the other to handle Zwave/Insteon, it would be nice to have the ability to share a PLM between more than one ISY. Basically, this could be accomplished by one isy talking to another. 

 A second benefit would be if you have 2 PLM's and one goes bad (as it is inevitable) the defective PLM could be taken off line and the signals transferred to the 2nd PLM. A display would show which or both PLM's are activated. Since they are both connected to the network, the requests could be handled in that manner.  Or maybe the second PLM could be set up but deactivated until needed? This would be a benefit in remote controlled locations.  I did not see anywhere mentioning that this option is currently available. 

Just a thought

Don

[Techman]

Not possible, each PLM has a unique address. That PLM address is stored in each of the device's link tables.

When you replace a PLM, the new PLM's address is written into each device via the RESTORE PLM option in the ISY.

 

[Mustang65]

That would eliminate being able to have multiple PLM's, but it should still allow more than 1 ISY to communicate with a single PLM using the network to communicate with each other.

Don

[larryllix]

2 hours ago, Mustang65 said:

That would eliminate being able to have multiple PLM's, but it should still allow more than 1 ISY to communicate with a single PLM using the network to communicate with each other.

Don

I noticed that also. He seemed to express it backwards but the same principles apply. The PLM is programmed to respond to only one ISY on the serial port side. I have no idea what that i/f would look like. ISY must know all the PLM information to be able to know who said what.

Also, how would you arbitrate the sharing of a serial port? If an arbitrator box (RPi?) would do it it, it would be cheaper, and more compact and convenient, to get a second PLM.

[mwester]

The problem is that we're dealing with technology that was current back in the 1980s -- serial ports and RS232 communications.

Were one to redesign the PLM to be a networked device, then one could also redesign the ISY to scale up using the network.  For example:

1. it wouldn't be hard to imagine a master/slave ISY scheme, where one might take over the PLM if the other ISY fails.
2. it would be possible to support multiple PLMs on a single ISY (although that might require a larger/faster ISY underlying hardware device).
3. it would possible, although challenging, to have multiple ISYs and multiple PLMs cooperating to handle large installations.

Alas, we have none of the above, and Insteon/SmartHome has made it quite clear with their hack-y attempts to address the "two-years-and-dead" problem that they're not interested in any further development of the PLM (I suspect they think that would only encourage folks to NOT use their hub and cloud infrastructure -- they do seem very much to be treating UDI as a competitor, not a partner).

[paulbates]

There is a RESTful interface to the insteon hub. But the problem is that its polled, and a stack: 
Switch status change -> Insteon Network -> Hub-> first controller that makes a rest call  gets the message and its cleared

And the ISY doesn't support the hub currently.... That would be a great nodeserver. There really is not a good answer to this outside of messaging between ISYs using rest calls for variables (v4) or a Insteon hub nodeserver that supports this concept (V5)

Paul

[larryllix]

There is a RESTful interface to the insteon hub. But the problem is that its polled, and a stack: 
Switch status change -> Insteon Network -> Hub-> first controller that makes a rest call  gets the message and its cleared
And the ISY doesn't support the hub currently.... That would be a great nodeserver. There really is not a good answer to this outside of messaging between ISYs using rest calls for variables (v4) or a Insteon hub nodeserver that supports this concept (V5)
Paul

I see node servers being a great move toward making that a reality but having a third box for a basic ISY install is getting over the top.

Once a box that integrates ISY and Polyglot comes onboard it should be a definite good forward jump in the Insteon trail.

Sent from my SM-G930W8 using Tapatalk

[Mustang65]

I have  USB Wi-Fi modem that I use in my RV that allows me to change my MAC address of the modem. Try and find one now days, this one has to be at least 5-6 years old. The reason for getting this Wi-Fi modem was because the Camp Ground would cap your streaming, so I just change the MAC address and continue.. must be driving the network cops insane by now.

So what does changing the MAC address have to do with the PLM? Well, if Insteon/Smarthome allowed the user to change the MAC address, you could have 2 PLM's on the system with one inactive (backup) and a copy of the working PLM stored in it. Should the in use PLM go bad, you could disable the defective PLM (plugged into an Insteon On/Off module), activate the backup PLM (insteon On/Off module) change the MAC code on the inactive PLM to the MAC code of the defective PLM and activate it. Maybe even an ISY program that would handle the process when requested. The ISY's "A" port would have a 2 to 1 RJ45 connector

Maybe even a small microcontroller that the PLM would plug into and would convert the current serial data transfer method to a network connection (with Wi-Fi option?). A microcontroller connected to the ISY would convert its serial (Port "A") PLM data.  I would go with the add-on micro controller for the ISY in its current design.

Does anyone have the packet format for the ISY/PLM serial communications?

Just a thought

[paulbates]

17 minutes ago, Mustang65 said:

I have  USB Wi-Fi modem that I use in my RV that allows me to change my MAC address of the modem. Try and find one now days, this one has to be at least 5-6 years old. The reason for getting this Wi-Fi modem was because the Camp Ground would cap your streaming, so I just change the MAC address and continue.. must be driving the network cops insane by now.

So what does changing the MAC address have to do with the PLM? Well, if Insteon/Smarthome allowed the user to change the MAC address, you could have 2 PLM's on the system with one inactive (backup) and a copy of the working PLM stored in it. Should the in use PLM go bad, you could disable the defective PLM (plugged into an Insteon On/Off module), activate the backup PLM (insteon On/Off module) change the MAC code on the inactive PLM to the MAC code of the defective PLM and activate it. Maybe even an ISY program that would handle the process when requested. The ISY's "A" port would have a 2 to 1 RJ45 connector

Maybe even a small microcontroller that the PLM would plug into and would convert the current serial data transfer method to a network connection (with Wi-Fi option?). A microcontroller connected to the ISY would convert its serial (Port "A") PLM data.  I would go with the add-on micro controller for the ISY in its current design.

Does anyone have the packet format for the ISY/PLM serial communications?

Just a thought

 

So what does changing the MAC address have to do with the PLM?

Nothing. Insteon and the PLM utilize an addressed packet stream, but its a proprietary packet and signalling technology and does not follow ET or other MAC addressing schemes. As pointed out above, the PLM uses RS2323 serial to talk to the controller (ISY). Its point to point and the problem begins and ends there. 

Does anyone have the packet format for the ISY/PLM serial communications?

This is the official, published technical brief of Insteon "architecture"

Paul

 

[larryllix]

2 hours ago, paulbates said:

 

<snippage>

Does anyone have the packet format for the ISY/PLM serial communications?

This is the official, published technical brief of Insteon "architecture"

Paul

 

...and even then it is a Whitepaper which means a published idea and may not be close to what was implemented. We hope it is close.

[Brian H]

The six digit Insteon ID is a hard coded ID added  at manufacture. I don't believe it can be changed on the fly.

Not new but most of the data is still reverent. Except for later things like the I2CS protocol. That added a Check Sum to some of the messages.

https://cache.insteon.com/developer/2413dev-042007-en.pdf

http://cache.insteon.com/pdf/INSTEON_Developers_Guide_20070816a.pdf

I also would say trying to mix two RS232 signals from two ISY994i could be a challenge. Each ISY994i would not know the links from the other one and maybe over write them in the PLM.

[larryllix]

31 minutes ago, Brian H said:

The six digit Insteon ID is a hard coded ID added  at manufacture. I don't believe it can be changed on the fly.

Not new but most of the data is still reverent.

https://cache.insteon.com/developer/2413dev-042007-en.pdf

http://cache.insteon.com/pdf/INSTEON_Developers_Guide_20070816a.pdf

I also would say trying to mix two RS232 signals from two ISY994i could be a challenge.

I have networked serial ports a few times in my life. It takes co-operative software at the client ends as the signals  were just wire-ORed together with diodes and a pull-up (IIRC to negative= 1) resistor at the server end.

I created one with about 24 devices but the signal can get flaky with too many shared ports.