Pinout

This is the pinout used with the Arduino Mega 2560

To ease the pain of wiring this all to the arduino I created a pcb to function as a header on the Arduino Mega 2560. You can find it in the Github Repo and can order it online for example here.

Component	PIN	Arduino PIN
Push Button	LED +	3
	LED -	GND
	Signal +	2
	Signal -	GND
Ultrasonic Sensor	VCC	5V
	TRIG	9
	ECHO	8
	GND	GND
Piezo 1	S	A0
Piezo 1	-	GND
Piezo 2	S	A1
Piezo 2	-	GND
Matrix socket	1	22
	2	24
	3	26
	4	28
	5	30
	6	32
	7	34
	8	36
	9	38
	10	40
	11	42
	12	44
	13	46
	14	48
	15	50
	16	52
	17	53
	18	51
	19	49
	20	47