RJ45 to DB9 for ENVI Unit?

[Mark42]

I had to use the last (#3 on front panel) USB port on my HT2 for the ENVI unit. I still have 2 spare RS232 DB9 ports on the rear and would prefer to use one of those.

Has anyone seen a vendor for a plug n play cable?

Best Regards,

Mark

[mrhappy]

Are you any good at soldering? If so you can make one yourself http://e.inste.in/2008/06/15/interfa...er-to-your-pc/ with only a few components. Or even use http://www.sparkfun.com/commerce/pro...roducts_id=449 which I think you would only need to cut up a cat5 cable and solder a few wires to interface with.

Failing that try contacting Current Cost themselves as I believe they used to sell them, http://www.currentcost.com/contact.html i've found them to be pretty helpful with support.

[Mark42]

Thanks for the links. I have sent a query directly to Current Cost.

Mark

[rauscs]

Please post here if you get any info on the cable - I'm out of USB ports on my hometroller as well.

Steve

[Mark42]

I have ordered the Sparkfun RS232 interface device and will try to fabricate an RJ45-RS232 cable for the ENVI. I will post back with the results.

Mark

[rauscs]

I sent an email to the US distributer: info@powersave.us, and they have the RS232 cables. They asked me to order the USB cable on their website (www.currentcost.net) and send them an email afterwards with the order confirmation asking for the RS232 version instead. I'll post back once I get it in hand.

Steve

[Mark42]

Steve,

The Sparkfun widget arrived and I built the RJ45 - DB9 cable. I tested it with HyperTerminal using COM3 and COM4 on my HT2 at 57600 8/None/1/No Control. The XML data comes in no problem.

However, the CurrentCost plugin is not very happy. When I changed the com port from 6 (my HT2 USB) to 4 (or 3), the CPU goes to 100% and stays there. Disabling/enabling the plugin does not help, the HomeSeer logfile contains the expected initialization messages, no errors are thrown here. The data values never update.

I tried a HomeSeer shutdown/restart, this too had no effect. I did not try restarting the HT2. Everything goes back to normal by reverting to USB operations.

I wonder if the plugin is expecting the com port to have the control signals CTS, DTR etc? The USB interface may provide them?

Mark

[mrhappy]

What length of cable are you running?

My custom Serial>Envi interface has no problems with the plugin, and I don't use any of the control lines.

The only reason I ask the length of the cable is I have previously experimented with longer cables, whilst the XML output appeared valid it did not decode it correctly - quite why I don't know.

[Mark42]

<<The only reason I ask the length of the cable is I have previously experimented with longer cables, whilst the XML output appeared valid it did not decode it correctly - quite why I don't know.>>

About 8.5 feet, it was a 10' RJ45 cable before I modified it.

How long were your experimental cables? Are you interfacing to a HomeTroller?

Mark

[mrhappy]

I'm not interfacing to the HomeTroller - 8' does not sound that far but i've found the signal to be quite weak out of the back of the Envi, i've had better luck extending the serial cable after the converter rather than before. I tried some 30' cables and the output was about 75% illegal characters. The shorter the cable better the accuracy but I could still get some illegal characters down to about ~6' of cable. I'm now down to about 3' and it works fine for me.

The problem is the slightest illegal character throws the entire XML out of the window, I could tell if I opened HyperTerminal to the port even with shorter cables I had boxes or greek symbols in the string (maybe just one or two, but thats enough).

I'd be tempted to try a shorter cable if you have one...

[rauscs]

I did receive the RS232 cable a couple of days ago from the powersave folks - fast shipping, and it seems to be working as well as the USB cable was - I am still seeing big gaps in graphs, so now it's time to go figure that out.

[Mark42]

How long is the RS232 cable? Can you tell if any of the control signals are wrapped around inside the plug?

Late edit. I tried 'one more time' and suddenly my home built cable works just fine, not sure what changed.

I would say your solution of a DB9 cable from CurrentCost is the better solution (and possibly cheaper); the SparkFun device cannot be enclosed in a DB9 shell.

Mark

[rauscs]

The cable is routed behind some stuff, so I can't easily measure it, but it seems to be the same length as the USB one; around 8 feet. The RJ45 end looks the same as the USB cable (plain), and the DB9 end has a medium-sized shell (photo attached).