Breadboards are the electronic hobbyists editor, so to speak. They let you connect stuff together and try out different circuit ideas without soldering. Here’s a mini breadboard, with on the right the bottom view when its protective adhesive layer is peeled off:

As you can see, all the pin holes on the top are connected together in groups of five. Keep this in mind while looking at the complete circuit we’re now going to assemble:

(the above image was created with Fritzing, a very nice entry-level electronics design tool)

You can deduce how everything connects together from the above, but to get a real insight on how things tie together exactly, it’s better to look at the corresponding “schematic”:

The components here are not drawn to scale, but all the components are listed, as well as all the pins and all the wire connections. This is the definitive reference for this circuit.

It’s easy to make mistakes, in which case this thing won’t work, or may even get damaged. Here is a first step, with the main components, and the wiring needed for supplying power:

Note the tiny orange capacitor between the µC’s pin 6 and 7 (it’s not a wire!) and the red LED, which needs to be inserted with its longest lead pointing to the right, i.e. connecting to the white wire. When reversed, things won’t work. The µC’s pin 1 is on the bottom left.

You can check proper operation so far by connecting this to a USB BUB and powering it up – which should cause the red LED to light up. Here’ is the complete circuit, with the rest of the connections built up using jumper wires, a messy but very flexible technique:

Note that the placement of components and wires is slightly different from the Fritzing diagram. The result is the same, these circuits are equivalent with respect to the schematic.

That’s it. Our µC circuit is ready to go. Now we need to figure out how to make it blink.

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