So finally I received my new Raspberry Pi. This is a small, low power ARM linux board featuring a ethernet adapter, 2 USB ports and even a full-HD HDMI port for a mere $30!. Check out www.raspberrypi.org for more information.
After running XBMC on it (no mpeg2 decoding, lame) and trying it out as a NAS (no SATA interfaces, sloooow) i decided to use it as a combined hardware / software project.
Sparks all around
The energy company here in The Netherlands made the mistake to install a Kamstrup 162 J series meter in my home with an mysterious looking phone jack on it. The phone jack kept intriguing me day after day. A small investigation on the internet indicated it to be a serial interface to get the meter counters and LOTS more information.
This instructable describes all the hardware and software I used to create this interface. The end result will be nice looking graphs on cosm, a free data collecting service found on the internet.
What it will give you
At least you will have fun making this interface. It will teach you about the raspberry pi, compiling a C program, interfacing to your FTDI board. And when things start to work: ultimate satisfaction :^)
And last but not least: it wil make you aware of the footprint you leave on this earth. I wanted to understand how much resources our household uses and in time, reduce the amount of gas and electricity we use.
What you will need
* An electrical meter fitted with a P1 port. In my case this is a Kamstrup 162, other Kamstrups will most likely work in the same manner.
* Linux commandline experience.
* Some basic TTL electrical knowlegde.
* A working Raspberry Pi;
* A FTDI cable or breakout board (as found on Sparkfun);
* A mini-usb cable.
PS: Because Raspberry Pi is a long word, I will (lovingly) refer to it as rPi...