Hot wire (Heisser Draht)

software originally for http://www.kreativekiste.de/elektro/dem-heissen-draht-auf-der-spur

developed by Timo Denk (Nov 2014)

modified by Sebastian Sproesser (2015)

We use a Arduino Mega, a seven segment display and a LCD

Arduino wiring

Wiring of the hot wire

• 22: start
• 24: stop
• 26: mistake
• 28: buzzer
• A0: penalty time

In this implementation start and stop are interchangeable, we can begin from either side. We trigger the start/stop with our game loop.

Wiring of the seven segment display

45, 46, 47, 48, 49, 50, 51, 52 We use the library SevSeg available here

Wiring of the LCD

• rs (LCD pin 4) to Arduino pin 12
• rw (LCD pin 5) to Arduino pin 11
• enable (LCD pin 6) to Arduino pin 10
• LCD pin 15 to Arduino pin 13
• LCD pins d4, d5, d6, d7 to Arduino pins 5, 4, 3, 2

Serial communication of game state

When the game runs, we send the current state of the game via serial connection to use a bigger display powered by a Raspberry Pi.

All messages have the format

mm:ss:xxx;mmm;status

• mm: Minutes
• ss: Seconds
• xxx: Milliseconds
• mmm: Current count of mistakes
• status can be:
  • Start: The start of a game (take note of the special case)
  • Reset: The player has gone back to the start
  • Time: Nothing happened, we just send the current time every second
  • Mistake: A mistake was made1
  • Stop: The player has completed a run

Special Case: When the status is "Start" then the time in front of it is not the current time (which is 00:00.000) but rather the penalty time of this run that is added for each mistake made.