Speed climbing is about tenths of a second, so the wall needs a proper clock. Timeotron 3000 is a small microcontroller board with two buttons, start and stop, and a large display built from eight 8×8 LED matrix modules (MAX7219, 4×2) driven through the MD_MAXPanel library.
At power-up it runs a quick display test (00.0, 11.1 … 99.9). Start begins counting and the display shows the elapsed time to a tenth of a second (SS.T). Stop freezes the result on the display until the next start. Buttons are debounced with the EasyButton library.
It was the first of the timing devices for climbing gyms that later became part of Backdoor.