33. case 30 Reaction Time Tester#

33.1. Reaction Time Tester#

  • Test yourself with this Python-based mini-game for the micro:bit and OLED! Written by Jensen from Raffles Institution.

33.3. Goals#

  1. Assemble a reaction time tester.

  2. Try not to break it when testing yourself!

33.4. Materials#

  • 1 x Tinker Kit (or OLED display)

  • 1 x Brain

  • 1 x You

33.5. Hardware Step 1 – Input/Output#


  • Attach the MicroBit to the Breakout Board.

  • Connect the LED to pin 12, which is a digital pin.

  • Connect the light detector to pin 8, another digital pin.

  • Brown to G (ground), red to V (voltage) and orange to S (signal).

  • These tell us if light is on or off.

  • Connect the OLED display to the I^2C pins. Any one set will do.

  • Connect your micro:bit to the computer, and download the Mu Editor.

Step 2 – File Transfer#



  • We need to download some modules to be used in the project.

  • From This link, download the module as a zip file.

  • Write the code (first screenshot) in Mu Editor to import the files.

  • Be sure to have the files in the same folder as the project.

  • Transfer a few of the files from your computer to the microbit.

  • On Windows, be sure to put the files in a folder under users/”Username”/mu-code for them to be detected my mu-editor.

  • These files are the modules that are not originally present on the micro:bit for you to import.

Step 3 – Loading Screens#


  • This step isn’t really necessary , but it adds a little flair into your project.

  • We display this loading on the OLED module

  • Using the module “add_text”, we can display text and other characters onto the display

  • We show the animation using the function “loading_screen()”

  • If you want more variations of the loading screen, head down to the bottom of the post.

Step 4 – Code the Game#


  • Here’s the actual test itself.

  • First, we have to have a time to wait before showing the indicator for the player to press the button.

  • We randomly generate the number and parse it into milliseconds by adding “000” to the end of the number after turning the original number into a string.

  • The variables time1 and time2 refer to 2 arbitrary points in time before the “#” ( the indicator to the player) symbol is shown.

  • One quirk about micropython and the MicroBit to note is that the time module is replaced by the utime module, and utime has to be imported instead of time.

Step 5 – A Little More Logic#


  • This is the step where we calculate and display the player’s reaction time.

  • This is done by calculating the time between when the indicator is displayed and when the player presses the button.

  • Then, we display the player’s reaction time to the OLED display.


33.6. Bonus loading effects:#

  • This one utilizes the light sensor and the LED to start the game.

  • It detects light and once the light is covered, the game will start.

This next animation is simple: display the characters “3”, “2” , and “1”, as a countdown before starting the game. The code is pretty self explanatory.