Your leaking thatched hut during the restoration of a pre-Enlightenment state.

 

Hello, my name is Judas Gutenberg and this is my blaag (pronounced as you would the vomit noise "hyroop-bleuach").



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decay & ruin
Biosphere II
Chernobyl
dead malls
Detroit
Irving housing

got that wrong
Paleofuture.com

appropriate tech
Arduino μcontrollers
Backwoods Home
Fractal antenna

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Like my brownhouse:
   sundown behind the house at four
Saturday, March 7 2015
It was sunny enough today that I didn't have to start a fire in the woodstove. The temperature outside was still unseasonably cold, as it's generally been since early January, but the sun is strong at this time of year and stays in the sky a long time. After Saturday morning coffee, Gretchen spent most of the day down in the greenhouse, where she eventually fell asleep. She didn't come back until after 5:00pm. (From the perspective of the greenhouse, at this time of year the sun sets behind the main house at about 4:00pm.)
This evening I made a little more progress on my somewhat-mothballed project to build an anemometer/wind direction sensor using only an array of barometric sensors. To get this system to work, I will need to use five digital barometric sensors. But since they all use I2C interfaces and have identical addresses that cannot be changed, I will have to build a way to multiplex an I2C bus between a microcontroller (probably an Atmega328) and the sensors. I have an ADG508F, a linear integrated circuit that can switch one wire between eight different other wires. I figure that if I switch the I2C SDA signal, I can leave the SCL common between all the sensors. (I did something similar to this a few years ago when a long-distance I2C bus proved noisy, and I wanted to connect to it only when reading the sensor at the other end of it. That time I used CMOS 4066 Quad Bilateral Switches, though I switched both SDA and SCL signals.) Getting all the wiring soldered into place is going to take some time, and it doesn't help that my eyes aren't what they used to be. But I've found that if I use my bifocals, a lot of overhead light, and a good soldering iron (not the one I recently bought at Sears), I can still make competent solders, at least when working with the 0.1-inch-pitch stuff that I grew up with.


For linking purposes this article's URL is:
http://asecular.com/blog.php?150307

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