Week 1 Homework

Videos and Notes

I'm a bit lost. I have no experience with hardware whatsoever so this could be totally wrong, but here's what I've understood so far: 

  • A breadboard has a + and - on both sides of it. The minus is for ground and the plus is for power. 
  • Power is generally associated with red wiring and ground is for black wiring (this also matches with the two leads from a multimeter)

Here's what I don't get: 

  • How do you know which lead of the multimeter to use on which part of the circuit? The video shows an example where switching the leads gets you a negative number, that should always be the case right?

Lab 1 - Components

I didn't see a datasheet in the Adafruit kit, but I'm guessing we don't need it for these components? Might have to do a Google search for some of the components.

I got the Adafruit kit that was recommended and while I found some of the pieces (lots of LED lights), I didn't see things like the voltage regulator and a few switches. 

Some of the components from the Adafruit kit. Not pictured: Arduino and the breadboard

Some of the components from the Adafruit kit. Not pictured: Arduino and the breadboard

Lab: Setting a Breadboard

First circuit ever!

Materials for it - wires, breadboard, wire stripper, multimeter, voltage regulator

Materials for it - wires, breadboard, wire stripper, multimeter, voltage regulator


I don't have the soldered DC power jack (the shop didn't have them either), so I don't know how far I will be able to get in this lab (Edit: an awesome second year suggested using the Arduino to power it so it WORKED). The goal is to set up a breadboard with an independent power supply (8-12V) through a 5V Voltage Regulator (7805).

I got my wires connected from power and ground (green for ground, red for power) and hooked up the volt regulator. I'm guessing the third pin is on a neutral line to avoid overpowering it?

Wiring setup

Wiring setup


So from what it looks like, I have a power and a grounding cord connecting from the Arduino to once side of the board, which is then connected to lines 2 and 3 respectively to power those lines and the pins on the regulator. I then connected the grounding and power from the right to the left to power the other side of the board so the whole breadboard is powered up. 

So now I create my circuit by connecting one end of the resistor to power to reduce the charge so that the LED doesn't short out (voltage is constant, so according to the formula V = IR, current and resistance are inversely proportional). Note to self, short end of LED goes to ground and long pin to power and IT WORKS!

Success!

Success!

Hooray! The resistor I used was not 220 ohms but 10000 (assuming I translated that correctly), which probably impacts the brightness of my LED. 

Lab: Electronics and Lab: Switches

I was able to get the circuits working but had no idea how to measure the amperage. I'm not sure why. Getting the circuits to work was fairly easy and I finally got the hang of how the current flowed