Dale-

Its still a solution, regardless ....

'There is no workable solution' .......except for this one which also looks like it would be compatible with the 2413U My posts to this thread were to just foster some discussion and engineering around the problem. I do agree that the bus vs point-to-point communication was always going to be an issue. I just wanted some idea of how to get around it. Thats all

You're right, I was wrong and its a typo in my picture and text. The cable is actually using pins 1,7,8 and not 1,2,8. So I still have the right cable. Update, I believe 'MrWorf' from this thread is very close to having a solution for the 2413U. I think this maybe the only way to engineer our way out of this issue.

I appreciate the valuable input and information. Attached is a picture of my current setup where I'm trying to engineer a solution to fix the problem. So far no success so im going to be trying the Raspberry Pi Solution next.

Victor I like the idea but Ive already tried that approach, The first link you shared is a USB to Cisco console cable, which is a rolled cable, meaning all 8 pins for the serial side are rolled in the opposite direction. Unfortunately this didn't work for me, It has to be a straight through cable leveraging pins 1(tx),2(gnd) 8(tx). I also have a USB to Serial RS232 straight through adapter and this has also failed. So there is something I'm missing.

Yeah, not useful,.... I asked a question, you ignored it, all the information was there, see what I typed, Read it. Further more, you're making numerous assumptions. Anyone else with an actual engineering idea before I go down the Pi path?

I recently bought an ISY994i also only to find out that the 2413S is being discontinued. So I'm looking towards Universal devices to help us come up with some kind of solution for us new users to jury rig the 2413U into the ISY994i I'm finding it hard to believe that the 2413U cannot be linked in some way with the ISY994 considering that the internals of the 2413S and the 2413U are not that different, other than a direct serial interface or the U providing serial RS232 communication over the USB bus. Both offer an RS232 communication, all be it that the 2413U provides that over the USB bus at 19,200 baud, so one would think that a USB to Serial cable could be used convert the signal from USB to serial RJ45 3pin. BUT I found out that the 2413U doesn't provide +-5v over the USB interface which is what would be needed to power a USB to Serial cable converter. Like an equivalent prolific PL2303 USB to serial adapter: https://www.amazon.com/Sabrent-Converter-Prolific-Chipset-CB-DB9P/dp/B00IDSM6BW/ref=sr_1_3?dchild=1&gclid=Cj0KCQjwl_SHBhCQARIsAFIFRVWem8ngyWfKA-IMY1EvO9Bus-4a4oaZcjgQ9tlSbCbxnnvZX2hZOBsaAthGEALw_wcB&hvadid=174229528311&hvdev=c&hvlocphy=9007584&hvnetw=g&hvqmt=e&hvrand=15922817551577557036&hvtargid=kwd-1923584537&hydadcr=24627_9648891&keywords=usb+to+serial+cable+adapter&qid=1627246829&sr=8-3 So I purchased a powered USB HUB, the hub would provide the +5v to my USB to serial cable converter, however when I connected it all together, still no luck, the ISY boots fine, no error lights, solid blue power light, log into the admin portal and the diagnostics in the ISY still says that the PLM is still not connected. I'd like a response from Universal devices on what we would need to do to get the ISW994i zw+ IR /PRO connected with a Insteon 2413U. Even if its some technical babble that we could take to an electrical engineer and get a custom adapter made up because I feel that I wasted $200 on an ISY that I can now never use. UPDATE: Universal devices, please tell me that this is not the only way to solve the problem?!? https://github.com/mrworf/serial-bridge