Added initial PWM code

validate.py

@@ -2,6 +2,10 @@
 
 import sys
 from datetime import datetime
+import time
+import RPi.GPIO as IO
+
+MOTOR_PIN = 19
 
 def timestamped(s):
 	"""
@@ -9,6 +13,25 @@ def timestamped(s):
 	"""
 	return "[{:%Y-%m-%d %H:%M:%S}] {}".format(datetime.now(), s)
 
+def setup_pwm():
+	"""
+	Performs initialization for pulse width modulation.
+	Returns the PWM object for the motor pin.
+	"""
+	IO.setwarnings(False)
+	IO.setmode(IO.BCM)
+	IO.setup(MOTOR_PIN, IO.OUT)
+	p = IO.PWM(MOTOR_PIN, 100) # Second argument is frequency, I think
+	return p
+
+def unlock_door(p):
+	"""
+	Uses PWM to turn the motor connected to the door handle.
+	"""
+	p.start(50)
+	time.sleep(1.0)
+	p.stop()
+
 def read_loop():
 	"""
 	Simple REPL skeleton for validating scanned IDs.
@@ -16,6 +39,8 @@ def read_loop():
 	# Open the log file in append mode
 	log_file = open("./access.log", "a")
 	log_file.write(timestamped("=== Door security initiated ===\n"))
+	# Initialize the PWM pin
+	pwm_pin = setup_pwm()
 
 	# Begin the loop
 	while True:
@@ -34,6 +59,7 @@ def read_loop():
 			log_file.write(s)
 			# TODO: Play open tone
 			# TODO: Run unlock procedure
+			unlock_door(pwm_pin)
 
 if __name__ == "__main__":
 	read_loop()