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First Circuit

Before this: Tools

Next steps: Gates and Wires

Your first circuit is a chip with one pin in and one pin out, and nothing between them but a wire. You will wire a switch to one side and a light to the other.

Contents

switch Enabled -> chip a
chip b -> light Enabled

Code

@left in a: bool
@right out b = a

@left in a: bool puts a pin named a on the chip’s left side. It takes a bool: on or off. @right out b = a puts a pin named b on the right side and gives it whatever arrives at a.

What does the light do when you flip the switch?

Run

  1. Compile the example and paste it in-game. The chip has a pin labeled a on its left and one labeled b on its right.
  2. Place a Switch to the left of the chip and a Point Light to the right.
  3. Wire the Switch’s Enabled output to pin a.
  4. Wire pin b to the Point Light’s Enabled input.
  5. Flip the switch. The light turns on and off with it.

Under the Hood

Open the chip. Inside there is only a wire from a to b. The pins on the chip’s sides are rerouters: @left and @right each add one. Leave the side annotations off and the chip has no gates at all. The source decides which pins a compiled chip has and what connects them.

The rerouters are why the side annotations exist. Your wires end on them, not on the chip, so they work as a socket: to replace the chip, break it and paste the new version over the same rerouters, and the wires stay as they were.

Modify

  1. Replace the Switch with a Button, wired from its Held output. Now the light is on only while you hold the button.

  2. Give the output a label of its own: @label("Light") @right out b = a. The pin’s floating label now reads “Light”.

    @left in a: bool
@label("Light") @right out b = a

  3. Flip the light: change the output to b = !a. ! is NOT, so the light is now on while the switch is off, and off while it is on.

    @left in a: bool
@right out b = !a

    Compile it, break the old chip and paste the new one over its rerouters. The Switch and the light stay wired. Open the chip again: the wire now passes through one NOT gate.

Make

Make a chip with two inputs and two outputs that passes each input straight across to its own output, then wire two switches to two lights through it.

switch1 Enabled -> chip a
switch2 Enabled -> chip b
chip outA -> light1 Enabled
chip outB -> light2 Enabled

Next: Gates and Wires.