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shivering with nothing to do
Monday, February 15 2016
I had another two hour session with my mentee today, and, unusually, it happened in the morning starting at ten. The poor kid is shy and doesn't ask for help even when his efforts are fruitless. Today I had to ask him several times if he was doing okay, and of course he wasn't. And so then I had to help. We're still working on a basic editor allowing players to be added to a game, and it's been going on for three or four sessions. The kid really should be doing some of this as homework, but his life overscheduled and underhoured, so I'm understanding of the underwhelming effort he is putting into our project.
Early this afternoon, despite continued brutal cold, I set out on a firewood-gathering foray into the forest, eventually cutting up a surprisingly-dry piece of Chestnut Oak a little above the Stick Trail a quarter mile from home. Today's haul came to 119.15 pounds. Usually the dogs don't come with me on a firewood foray that happens after their morning walk, but their walks have been so brief due to the cold that today they were eager to join me. But I felt bad for Eleanor as I cut up the wood and loaded it on my pack. She stood there with nothing to do, shivering in the cold. Temperatures at the time were in the upper teens.
This afternoon I attempted to determine which of the pins connecting my Raspberry Pi to my HDMI touchscreen were actually needed to get the touchscreen to work. So I detached the two components and used jumper wires to reconnect various systems, starting with the wires needed by the SPI serial bus (which I knew to be the technical basis for the touch sensor). But evidently those weren't enough. So then I began attaching other wires. But I was working in imperfect light with two boards that kept rotating with respect to each other using short (10 cm) wires and somehow inevitably I managed to run wires between the wrong pins. At the next test, the Raspberry Pi refused to boot and I could smell a problem. Yes, smell. I immediately turned everything off and abandoned the experiment. That smell, by the way, was insulation on some of the jumper wires being excessively heated by a large current carried by the wire, the sort of thing that happens when 5v or 3.3v gets connected to ground. The switching power supplies inside tiny modern wall warts can source a frightening amount of power if asked to do so.
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