Javad Hamidi

Creating Logic Circuits in Powder Toy

· Javad Hamidi

Despite having an entire category of materials devoted to electronics, making logic circuits in The Powder Toy is surprisingly hacky - although definitely possible! Here’s a demo I made where the flag only lights up for input 0100111. Let’s go through some tricks to make your own …

Make sure you understand what logic gates are and how they work before continuing!

Also, familiarise yourself with these handy Powder Toy shortcuts. These will help a lot!

Designing a Logic Circuit

Before jumping into Powder Toy, make sure to get/design a circuit for reference. I used Logic Friday for creating a truth table and then generating a gate diagram (just be wary of dodgy download links). Here’s an example:

Diagram from Logic Friday

Making Logic Gates

The diagram below provides a guide to creating each of the five main gates used in the demo. The goal was to fit each of the basic logic gates (OR, AND, and NOT) in a 4×7 rectangle of blocks, while NAND and NOR are just a composite of a NOT block with an AND and OR respectively. These gates should work without interference even when stacked directly on top of each other.

Common Logic Gates Diagram

If you want to understand or customise these gates, then here are some tips that might help …

  • Leaving a single block space between conductive blocks produces some strange properties. One block of empty separation vertically or horizontally will still conduct, but a diagonal separation of one block won’t work. An insulator in-between will also still block the flow of electricity.
  • Creating an OR gate is extremely simple and can be done a variety of ways; there’s nothing too special about the materials chosen here or how they’re spaced out.
  • The AND gate works thanks to the NTCT material, which only conducts when it is hotter than 100 degrees. Here, both input wires need electricity for the block to get hot enough to become conductive.
  • The NOT gate works the opposite way; using a PTCT block that needs to be cooler than 100 degrees to conduct electricity. So when there is input, the block will get too hot and stop conducting, but when there’s no input, the block will be cold enough to pass electricity a the battery block (BTRY).
  • The NAND and NOR gates use a more compact, 4×7 variant of the NOT gate, but it can be a little less reliable than the 5×7 one provided.
  • The insulating material (INSL) around the edges of the gates is largely cosmetic, the insulators within are not!