checkpoint4_3.py

import webiopi
from webiopi.devices.digital import PCF8574A
mcp = PCF8574A(slave=0x38) # 0111000

GPIO = webiopi.GPIO # Assign webiopi library to GPIO object

leds = 4 # number of led outputs in total
SWITCH0 = 4 # Set  Switch value to P4

for index in range(leds):
  mcp.setFunction(index, GPIO.OUT) #Set pin at index as output
  mcp.digitalWrite(index, GPIO.HIGH) # Turn n LED at index

mcp.setFunction(SWITCH0, GPIO.IN) # Set SWITCH as input

"""
   Function to toggle logic
"""
def toggleLED(): 
  while True: # Always run loop
    mcp.portWrite(0x0F) # Set P0-P3 as high 1111
    if (mcp.digitalRead(SWITCH0) == GPIO.HIGH):
      mcp.portWrite(0x0E) # Set P0 low P1-P3 as high 1110
      webiopi.sleep(0.5) # Wait 0.5 second
      mcp.portWrite(0x0A) # Set P0, P2 low P1 P3 high 1010
      webiopi.sleep(0.3) # Wait 0.3 second
      mcp.portWrite(0x0D) # Set P0, P2, P3 high P1 low 1101
      webiopi.sleep(0.5) # Wait 0.5 second
      mcp.portWrite(0x00) # Set P0-P3 low 0000
      webiopi.sleep(0.4) # Wait 0.4  second
    mcp.digitalWrite(SWITCH0, GPIO.LOW) # Write assigned value to SWITCH0 output (negative logic)
toggleLED()

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