Re: Heating controller protocol

[watson2@xxxxxxxxxxxxxxxx]

Hi Raymond,

I'm posting here just in case anyone else is interested... I'll send the
attachments just to you separately via email:

I got a doc that described the old heatmiser protocol and then wrote the
simple C program to experiment and found a couple of differences - I
think I have the newer ones which allow time to be set over the wire as
well so there appears to be a few differences but not many. i.e. whoever
contributed/wrote the original protocol doc did all the hard work!

I've attached the doc I received (Heatmiser Protocol v0.3.doc)

I've also attached my very simple heatmiser command line program. I
intended to clean this up etc. etc. but I thought you might appreciate
seeing it regardless of the state because I have not yet updated the
Protocol doc to version 0.4.

Most of my testing has been done with the PRT-N/HW (with some PRT-Ns)
and I used a 232<>485 converter: ebay 150190398813 is an example
(from
the people I randomly chose to get mine from - ymmv).

The "server" is in the loft with the 232<>485 converter,
then the 485 is
connected to std cat5 cable, through 2 floors and a patch panel to
eventually hook in to the blue and yellow wires from the PRTs via the
UH1. From memory yellow connected to +, blue to -, but ymmv - i.e. my
memory might be shot. I also put a high value resistor (~2k) to connect
the ground of the converter to the -ve (0V) supply from the UH1 - just
to bleed out any differences in potential (not that there should be
much, but with laptop power supplies, you never know). Clearly this
isn't the right thing to do, but impatience got the better of me and I
thought it better doing it than not and frying my serial port.

The code was written on a linux box but is so basic and general that I
would imagine it'll compile on just about anything with no/minor
changes. I've put it under the GPL just to be clear that people are free
to use the code (and hopefully I'll get some useful changes back!) - but
I'm not sure how I "release" the code, web pages, updated
protocol etc.
etc. to a wider audience.

to get you going:
gcc hm.c -o hm; ./hm scan 0 0

If you find it useful, just let me know and I'll pass on the changes I
make in future.

Cheers, Bruce.