Read Commercial Heat Meter via IR

Here is a shot in the dark on the feasibility front.

I have some heat meters installed like this

The data can be read by interrogation with an infra red sensor.

Has anybody had experience with this type of meter, and been able to use an Arduino to extract the stored data? I don't want to open them up and tamper with them.

I don't suppose there are any downloads with the protocol structure already? It is using a standard irDA interface, I would start with that:

First will be determining which method it using. If you are lucky, it will provide some type of response to errors which will help you figure that out. There is a Discovery mode of IrDA, which might be useful to interrogate an address response. That will get you started.

Thanks. All I have is the commercial software and USB cable with IR head. The software does work but is absolutely abysmal and slow to use. My current Arduino is essentially a replacement of the commercial meter.

Ahh... well right there, you have everything you need! Using the software and IR head, you need to take a look at the transactions going on between them to reverse engineer the protocol.

Then it is very (relatively) simple from there.

IrDA is essentially a serial replacement, so the IR head probably shows up as a com port in your device manager. You can find serial snooper programs which will allow you to see what is going back and forth on that port. Then, once you know how to initialize communication, send commands, and receive data, you basically just use an IrDA module on the UART of the Arduino to do the work.

Retroplayer: Ahh... well right there, you have everything you need!

You can find serial snooper programs

Thanks. I note the (relatively) with some apprehension, but "serial snooper " may be the magic words!

At least this is one I can take slowly. Getting Arduino up to do the same job better is the priority.

If you can get the arduino speaking with the computer over serial, you can do it. Like I said, IrDA is typically used as a serial replacement. The hardest part is reverse engineering the command structure and since you already have the tool to talk to it, you just made the job as easy as baking a cake. Wait… I can’t bake a cake. hmm… :wink:

Seriously, though, that is the hardest part. Just imagine if you didn’t have the tool and were trying to go in blindy sending commands and hoping for a response and trying to figure it out that way!

Thanks. I understand your approach is: - the IR head is enabling conversation. The task is to listen in on that conversation at the USB port, COM3.

Yep. Exactly. A serial snooper or serial sniffer is what you need. I have also seen it referred to as a virtual com port which sits in between the computer output and the device input (IrDA head). There is software to do this, or if you have something like the "bus-pirate", you can do it that way as well.

Once you have the command structure, it really is all downhill from there.



Good luck. Just PM if you need any help.

Hi Did you have any luck cracking the code and anything you may be able to share with me. Thanks.

I'm afraid not. Other priorities have gotten in the way. I would like to pursue this. The stock IR reader died and it cost me $200 to replace, so I'm far from impressed but I don't really have the expertise.