Household electrical wiring (the same which powers lights and appliances) is used to send digital data between X10 devices. This digital data is encoded onto a 120 kHz carrier which is transmitted as bursts during the relatively quiet zero crossings of the 50 or 60 Hz AC alternating current waveform. One bit is transmitted at each zero crossing.
I was wondering if anyone has created any hobbyist X10 to serial/spi/i2c modules or anything of the like. There are tons of commercial dongles that are $10+ for receive or transmit only. However I haven't found anything that lends itself to open source design.
X10 doesn't necessarily need to be the exact protocol used, just anything that functions like it. I am just looking for something that allows basic communication over in-home wiring/power lines.
Yay, thanks for the link I started receiving alerts (email) from my linode that my usage was higher than normal. I'm at work so I can't log in to see whats up, nice to know that the hackaday traffic is the cause.
Thanks for the positive feedback =) The truck is a 2007. I wasn't expecting a monolithic board for the whole cluster either. Funny thing about these particular trucks is this gauge cluster actually contains the odometer for the car - if your gauge cluster goes bad it has to be replaced and your mileage is reset and must be factory reprogrammed with the correct mileage. Evidently the Lamps on the gauges go out pretty often and this is an expensive replacement as the local dealers wont replace individual bulbs, only the whole cluster. So replacement comes with cost of the board, labor for physical replacement and the cost most dealers charge ($100-$250) just to hook up to their programmers. To get a few bulbs replaced - this costs the uninitiated $500-$1000.
I'm not sure on the cost for the actual production - but an individual gauge cluster costs over $250USD not including labor to replace. But yes, the edges are irregular. They are rounded all the way across the top and then some notches and holes all throughout. The **edit** attached images should show this nicely
Also notice, the front is white and black, but the back is still green. I believe SEEED Studio actually has a selection of colors for PCBs as well though. I guess I never really thought about it being strange. I am an IT guy and not an EE, goes to show my naivete with electronics.
My buddy has a diesel Chevy truck that has 'old ugly amber lights' in the dash that match no other part of the lighting on the car from the stereo to the push button indicators - the color also does not match the light on his a-pillar boost or egt gauge. We found a brief instruction (text only) on how to do the mod for previous year trucks. We set off and made a reasonable tutorial for this truck. Abstracting the steps we went through - it should work on nearly any car or truck as well.
Some of the pitfalls we ran into were the orientation of the original lamps/bulbs was not uniform. Each lamp/bulb had two of four leads soldered to the gauge cluster, and we found no pattern. We used a simple multimeter to figure out which side was hot and marked them accordingly.
We will be making some other (electronic) mods to this truck later as well. Hopefully things like this interest people on here. If not, I'll stick to the uC and logic projects =)
I've been thinking about re-doing the project with different LEDs to try to get rid of the 'hot spots' of light behind the gauges, but I'm not sure what would work out best. I was thinking even shaving/filing down the rounded tip of the LED to diffuse the light a bit more, but I'm not sure on effect as a whole.
I applied power to it and it didn't give up any black smoke. I haven't downloaded the development environment for it yet. Mainly, I've been reading about them and trying to figure out what I need to do other than the initial blinky light/hello world. I have never done any CPLD/FPGA work before, so this will be a first for me.
I've been, primarily, a software guy up until recently - so this is the perfect free PCB for me. Maybe this will help me to transition out of the arduino crutches into something a little more serious.
I received my Lattice CPLD Free PCB a few days ago. I had the parts on order from mouser a week or two before. The build went ok for my first time ever using 603 size components. The lattice CPLD IC was a reasonable package size and I have used ICs with higher pincount before. I used the drag soldering method because my solder was of improper size to do individual pins, and drag soldering is just plain easier.
Here are the images - one by itself and the other next to my handy bus pirate:
