VoJT4′s first foray into micro-controllers involved taking a Launchpad and hooking it up to count lap times for his slot car setup. The LCD is based off a HD44780 controller. The current version displays laps and lap times with a push-button to control the timer. This is also his entry into the June 2011 Project of the Month contest.
Car is detected by magnetic Reed switch (extracted from old keyboard) placed under each lane. I needed to use capacitor in parallel to the switch, otherwise many false interrupts were generated (one car triggering both lanes,…). TimerA is used to track time with interrupt generated 100 times per second.
Code and Schematics can be obtained in his Forum thread.