Simon Says Project from the March 2021 Alien3D Ufo

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Earlier today, I posted the print results from the March 2021 Alien3D UFO subscription box. Now it is time to look at the project included in the UFO. The project revolved around the very excellent Simon Says game created by DIY Machines. I won’t do a step-by-step of the project. Instead, I will focus on the few variations I did on this build to get the project completed to my satisfaction.

Hardware included with the box.

Hardware to build the Simon Says.

The following hardware was included with the UFO to build the Simon Says:

  • 1 Arduino Nano clone.
  • 1 Micro USB cable (only used to program the Arduino)
  • 4 LED 30mm Buttons. These were snap fit.
  • 4 220Ω resistors.
  • 1 Buzzer.
  • 1 OLED screen.
  • 1 ON/OFF switch.
  • 2 AA Battery Packs. These both had ON/OFF switches.
  • Wires

In addition to the above hardware I used the following items to build this project.

The links below are Amazon affiliate links.

Printing the case

I printed the case and lid downloaded from the Alien3D project page. Note, if you have the arcade buttons that are press-in, you have to use the large version of the lid. If you print the standard version, it will still work. A bit of hot glue will hold it in place.

The lid was printed using Sapphire Blue PolyTerra PLA from Polymaker. The case printed used Real Red from 3D Solutech. Both prints came out very nicely.

Render of the spacer I created for the Simon Says case.

I did not use the Arduino standoff included with the original files from DIY Machines. It wouldn’t have worked with the way I set things up.

I did run into space issues later on when assembling the project. The battery case provided by Alien3D was larger than the ones called for in the original plans. Plus, I kept the headers on the Arduino and used Dupont connectors. These variations meant the case was too short to close. I did some editing in MeshMixer to create a spacer between the case and lid to fix this. I ended up using two of these spacers in my finished project.

The spacer I created can be downloaded from

I printed both spacers with PLA+ from GST3D. One was printed in Apple Green and the other in Yellow.

Testing it out on the breadboard

I usually try to test every project out on a breadboard before assembling it. There is nothing worse than finding out problems after all the soldering and assembling has been done. For breadboarding, I did not hook all four buttons up. Instead, I hooked each button up one at a time to Arduino pins D12 & D8. That was enough to show whether the button and its LED worked adequately. Luckily everything worked as expected.

Breadboarding the Simon Says.

Here is a video showing the test for one of the buttons. I did the same test for each button. I was basically looking to see if the light and game reacted when I hit the button.

Testing the game on the breadboard.

Assembling the project

Dupont connectors hooked up to the Arduino Nano.

I followed the Instructable created by DIY Machines to assemble the project. As noted previously, I did make a couple of changes to the project. First, I decided to use Dupont connectors to the Arduino. I did this partly because the Arduino had headers on it. I figured I might as well give my shaky fingers a workout crimping small pins instead of soldering small wires. I would not recommend using Dupont connectors if anyone will bang this around a lot. If I thought this would take abuse, I would have stuck to soldering.

For the two sets of wires going to the buttons, I used four-pin Dupont connectors on the Arduino side. I happen to be running out of single-pin housings. Using four-pin housings worked out pretty well. It just meant making sure to keep wire pairs straight when doing so.

Other than the connections going to the Arduino, everything else was soldered. I also put shrink tubes over all solder joints where I could.

One area I could maybe see confusing for people would be the use of a different arcade button. Electronically the button provided is the same as the one from the original instructions. But the button provided by Alien3D did look slightly different on the bottom. Here is a look at how I soldered it.

Bottom of the arcade button.

The top pair, as pictured, is for the switch. The bottom pair, as pictured, is for the LED. The LED polarity is essential. Here is what is soldered where:

  • On the upper-left corner has the black wire soldered. The other end of the black wire went to the following pins on the arduino for each button:
    • Blue Button = D12
    • Yellow Button = D11
    • Red Button = D10
    • Green Button = D9
  • On the upper-right corner has one end of a 220Ω resistor soldered to it. Also soldered here is what I used as a blue wire (it was purple in the original plans). The other end of the purple wire for each button gets bundled together and connected to ground as explained in the Instructable.
  • The lower-left corner has the other end of the 220Ω resistor soldered to it.
  • The lower-right corner has the green wire soldered to it. The other end of the green wire went to the following pins on the Arduino for each button:
    • Blue Button = D8
    • Yellow Button = D7
    • Red Button = D6
    • Green Button = D5
Everything connected up.

I noted previously that the AA battery cases provided were different from those in the original Instructable. The AA battery cases have power switches on them, making them too big to sit down inside the case as designed. To get around this, I decided to create the spacer shown previously in this post. Using two spacers allows the batteries provided to be used. It also provides plenty of room for anyone that wishes to use the Dupont connector method. The batteries will now sit on their side instead of flat on the bottom of the case.

Four M2x20mm screws used.

I just noticed, looking at the picture, that I might have made one more change. I have the buzzer on longer wires to allow it to sit nicely in the bottom of the case.

Before proceeding to close up the case, I made sure to turn on both AA battery cases. I then used four M3x20mm pan head screws to secure the lid to the case.

Completed Simon Says game.

Testing the hardware and final thoughts

Here is short video showing the game in action.

Testing the Simon Says hardware.

I thought this was a great project. The minor issues I had assembling the kit were easily overcome. Actually, I saw those minor issues as challenges included in building the project. I also think it was kind of cool that both Alien3D and CyberCityCircuits provided two different takes on this classic game at around the same time. I can’t wait to see what the April project will be!

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