eBay has these chainable 8×8 led matrix (MAX7219) for fairly cheap.
I put together a sequence of 4, as that is all that would fit on my 3.5″ x 6″ protoboard. I connected an Extracore (mini-arduino), power regulator, thermistor and clock to make a tool to present data sent in from the USB connection. On the Linux side, I have a cron job running a php script to eat some data off a website and push it up to the board which presents the data in a loop.
After tweaking the font size, the 8×8 x 4 grids really only let me present about 6 characters and some punctuation. Enough for then. But now I want MOAR!
So, trusty OpenSCAD to the rescue!
These elements connect together and allow mounting of multiple MAX7219’s. I intend to link a set of 8 to get 12+ characters. Perhaps I’ll make a few more connectors to hold the other electronic elements, but for now, I just want the grid array with a 5 conductor link (VCC/GND/DATA/CS/CLK) that I can connect using I2C to whatever microcontroller.
You can see the in-wall toilet tank here (TOTO).
The small valve to the right of the red tank frame is a slow drip to the in-floor trap. This keeps the trap filled even when the floor drain isn’t often used. It will prevent bad odor from coming up through a dry trap.
I’ve been waiting a long time to raise the flagpole and today is the day.
I’m the son of a farmer and although trained in engineering principles, I usually like to over-engineer things for additional strength.
Here we’re filling the walls with concrete to unite the bricks and reinforcing steel into a single structure.
The socket in the ground for the flagpole has a centering cone for the pole itself and is intended to be filled with sand around the pole to absorb some shock and movement.
The socket is surrounded by concrete at a depth of 3.5 feet.
Rebar in and footing set. Now to let it dry and then build it up.
There will be a special floor drain with a slow drip (source feeder copper line is covered by the blue sheath, and drain is covered by foil tape in preparation for the concrete pour). This way, the trap below the floor drain will not entirely evaporate and vent the sewer into the bathroom.