kaypad.py

import time

lowpins = []
for i in [0,16,5,4]:
    lowpins.append(machine.Pin(i, machine.Pin.OUT))

highpins = []
for i in [14,12,13,15]:
    highpins.append(machine.Pin(i, machine.Pin.IN))

led = machine.Pin(2, machine.Pin.OUT)
for i in range(4):
    led.value(0)
    time.sleep(0.125)
    led.value(1)
    time.sleep(0.125)

matrix = [[1,2,3,"A"],[4,5,6,"B"],[7,8,9,"C"],["*",0,"#","D"]]
def getkey():
    for i in range(4):
        for j in range(4):
            lpin = lowpins[j]
            lpin.value(1)
            time.sleep(0.00125)
            if highpins[i].value()==1:
                return matrix[i][j]
            time.sleep(0.00125)
            lpin.value(0)
    return None

value = 0
while 1:
    key = getkey()
    if key is not None:
        if key=="D":
            a = 0
            b = 1
            for i in range(value):
                t = a + b
                a = b
                b = t
            print("fib(",value,"): ",a)
            for k in range(a):
                led.value(0)
                time.sleep(0.125)
                led.value(1)
                time.sleep(0.125)
            value = 0
        else:
            value = value*10+key
         
        time.sleep(0.25)