import RPi.GPIO as GPIO
class keypad():
def __init__(self, columnCount = 3):
GPIO.setmode(GPIO.BOARD)
# CONSTANTS
if columnCount is 3:
self.KEYPAD = [
[1,2,3],
[4,5,6],
[7,8,9],
["*",0,"#"]
]
self.ROW = [26,24,23,22]
self.COLUMN = [21,19,10]
elif columnCount is 4:
self.KEYPAD = [
[1,2,3,"A"],
[4,5,6,"B"],
[7,8,9,"C"],
["*",0,"#","D"]
]
self.ROW = [18,23,24,25]
self.COLUMN = [4,17,22,21]
else:
return
def getKey(self):
# Set all columns as output low
for j in range(len(self.COLUMN)):
GPIO.setup(self.COLUMN[j], GPIO.OUT)
GPIO.output(self.COLUMN[j], GPIO.LOW)
# Set all rows as input
for i in range(len(self.ROW)):
GPIO.setup(self.ROW[i], GPIO.IN, pull_up_down=GPIO.PUD_UP)
# Scan rows for pushed key/button
# A valid key press should set "rowVal" between 0 and 3.
rowVal = -1
for i in range(len(self.ROW)):
tmpRead = GPIO.input(self.ROW[i])
if tmpRead == 0:
rowVal = i
# if rowVal is not 0 thru 3 then no button was pressed and we can exit
if rowVal <0 or rowVal >3:
self.exit()
return
# Convert columns to input
for j in range(len(self.COLUMN)):
GPIO.setup(self.COLUMN[j], GPIO.IN, pull_up_down=GPIO.PUD_DOWN)
# Switch the i-th row found from scan to output
GPIO.setup(self.ROW[rowVal], GPIO.OUT)
GPIO.output(self.ROW[rowVal], GPIO.HIGH)
# Scan columns for still-pushed key/button
# A valid key press should set "colVal" between 0 and 2.
colVal = -1
for j in range(len(self.COLUMN)):
tmpRead = GPIO.input(self.COLUMN[j])
if tmpRead == 1:
colVal=j
# if colVal is not 0 thru 2 then no button was pressed and we can exit
if colVal <0 or colVal >2:
self.exit()
return
# Return the value of the key pressed
self.exit()
return self.KEYPAD[rowVal][colVal]
def exit(self):
# Reinitialize all rows and columns as input at exit
for i in range(len(self.ROW)):
GPIO.setup(self.ROW[i], GPIO.IN, pull_up_down=GPIO.PUD_UP)
for j in range(len(self.COLUMN)):
GPIO.setup(self.COLUMN[j], GPIO.IN, pull_up_down=GPIO.PUD_UP)
if __name__ == '__main__':
# Initialize the keypad class
kp = keypad()
# Loop while waiting for a keypress
digit = None
while digit == None:
digit = kp.getKey()
# Print the result
print digit
What I have tried:
I tried to convert the code but got a lot of errors; its urgent would be great if someone can help in converting the code for me