D&D Die Roller with Raspberry PI RP2040

Fantastical Project Built with MCU TFT Display and LVGL Graphics

- Andrew Levido

Dungeons and Dragons is a complex, fantasy role-playing game, in which various players roll polyhedral dice with 4 to 20 faces to determine outcomes at various decision points. Andrew describes an electronic device he created to simulate rolling the dice using a Raspberry Pi RP2040 MCU, a TFT with touchscreen to show the rolling dice and display the scores from each roll, and an STM amplifier to add the element of drama with sound effects.

My daughter is a big fan of Dungeons and Dragons, the fantasy role-playing game. This game has been around since the 1970s but has become hugely popular during the last few years. One of the key aspects of the game mechanics is the use of polyhedral dice to decide the outcome at various decision points. A typical set of dice, shown in Figure 1, includes seven dice. Six with 4, 6, 8, 10, 12, or 20 faces (designated D4, D6, and so on), along with a second, 10-faced die, the "percent" die. As the name suggests, the "D%" die is used together with the D10 to get a score ranging from 1 to 100 percent; one die gives the tens digit and the other gives the ones digit.

There is sometimes a requirement for a Yes/No decision. This can be done in various ways - for example by using a D6 and designating odd numbers to indicate a No and even numbers a Yes, or by using a special coin-like token. There is frequently the requirement to roll several dice and use the sum of their values to determine game outcomes.

If you look online, you will see that a plethora of beautifully decorated D&D dice sets are available. The die-rolling experience is an integral part of the enjoyment of the game, and the dedicated D&D aficionado will have several sets to choose from.