Working On Blum 'Arduino Basics' Video Tutorial #2

So tonight I had a chance to work on the exercises in the Jeremy Blum 'Arduino Basics' video tutorial #2 again.

I had started on the #2 video about a week back, but last week needed to return the borrowed Arduino components to the friend from whom I had borrowed them. The official Arduino Starter Kit I had ordered from Amazon showed up on Thursday. So I now had the parts I needed to resume learning about the basics of microcontrollers.

Finally, tonight I had the time to open up the kit and pick up sort of where I left off with the first exercise in Blum video #2. Before I started the video back up, though, I tried to put together the the laser-cut wooden base for the Arduino and breadboard. Annoyingly, the Italian Arduino folks seem to have either neglected to include the screws for attaching the Arduino to the wooden base, or they forgot to specify the size for those screws when they wrote the book that comes with the kit. The book says to fasten the Arduino to the base with three screws, but that's all it says. I guess that's part of the DIY aspect of the kit. If you want to screw the Arduino to the wooden base, figure out the screw size 'yourself' and get them 'yourself'...

After reviewing a bit of the #2 video, I hooked up the Arduino Uno Rev 3 to a breadboard, a 10K ohm resistor, a switch and an LED (light emitting diode). I watched what Jeremy did in the video, I connected the components with the jumper wires, then I rechecked to make sure everything was the same as in the video. One issue I didn't think about the first time I hooked up this circuit was whether it matters which way the current runs through a resistor or, said another way, whether it matters which lead on a resistor is connected to ground. I tried looking that up in the
SparkFun tutorial on resistors, but couldn't find the answer. I decided to just make sure it was hooked up the same way shown in the video, and I'll search later on Google to find the answer about whether resistors are ok with current going either way through them.

With all the components hooked up, I connected the USB cable into my laptop, then into the Arduino. The LED was supposed to only light up when I pushed the switch, but as soon as I hooked up the USB cable, the LED started flashing on and off. Drat! Didn't do that before when I hooked it up. Unplugged the USB cable, then hooked it back up again. LED still flashed on and off.

Then I realized it was a brand new Arduino Uno, fresh from the manufacturer, and it didn't have the Arduino sketch, or program, uploaded to it yet which would make the LED only come on when I held down the button. Once I uploaded the program, which I had written a week ago when I had the borrowed Arduino, the LED worked properly, lighting up when I held the switch down and going off when I let up on the switch. Success!

Getting late, so time to stop for tonight. Tomorrow I'll try to finish Blum video #2.

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