Chess Clock

https://youtu.be/9qv9F0zIUgI

An Arduino controlled chess clock.
The speed of the clock can be changed with a potentiometer.
High speed for reaction games.
t is the delay after each change of levels and allows the magnetic fields to build up properly. t=3 works for most stepper motors. Make sure your power supply is accurate and supplies 5 volts, 1 or 2 Amps. The Arduino sketch below makes it all work.

//Nano half step mode
//512 >> 360 degrees 1.4 step/degree
int Pin0 = 9; int Pin1 = 10; int Pin2 = 11; int Pin3 = 12;
int Pin4 = 2; int Pin5 = 3; int Pin6 = 4; int Pin7 = 5;
int ClockPin = 2; //change between the two clocks
int SpeedPin = 0; //adjust with the potentiometer
int t=3;
void setup()
{
pinMode(Pin0, OUTPUT); pinMode(Pin1, OUTPUT); pinMode(Pin2, OUTPUT); pinMode(Pin3, OUTPUT);
pinMode(Pin4, OUTPUT); pinMode(Pin5, OUTPUT); pinMode(Pin6, OUTPUT); pinMode(Pin7, OUTPUT);
pinMode(ClockPin, INPUT); pinMode(SpeedPin, INPUT);
}
void loop