# Raspberry pi GPIO
> [TOC]
###### tags: `Raspberry pi`

## LED CODE

import RPi.GPIO as GPIO            # import RPi.GPIO module  
from time import sleep             # lets us have a delay  
GPIO.setmode(GPIO.BCM)             # choose BCM or BOARD  
GPIO.setup(24, GPIO.OUT)           # set GPIO24 as an output   
  
try:  
    while True:  
        GPIO.output(24, 1)         # set GPIO24 to 1/GPIO.HIGH/True  
        sleep(0.5)                 # wait half a second  
        GPIO.output(24, 0)         # set GPIO24 to 0/GPIO.LOW/False  
        sleep(0.5)                 # wait half a second  
  
except KeyboardInterrupt:          # trap a CTRL+C keyboard interrupt  
    GPIO.cleanup()                 # resets all GPIO ports used by this program 

import RPi.GPIO as GPIO            # import RPi.GPIO module  
from time import sleep             # lets us have a delay  
GPIO.setmode(GPIO.BCM)             # choose BCM or BOARD  
GPIO.setup(24, GPIO.OUT)           # set GPIO24 as an output   
  
try:  
    while True:  
        GPIO.output(24, 1)         # set GPIO24 to 1/GPIO.HIGH/True  
        sleep(0.5)                 # wait half a second  
        if GPIO.input(24):  
            print("LED just about to switch off")  
        GPIO.output(24, 0)         # set GPIO24 to 0/GPIO.LOW/False  
        sleep(0.5)                 # wait half a second  
        if not GPIO.input(24):  
            print("LED just about to switch on") 
except KeyboardInterrupt:          # trap a CTRL+C keyboard interrupt  
    GPIO.cleanup()                 # resets all GPIO ports used by this program  

## Button

import RPi.GPIO as GPIO
import time

GPIO.setmode(GPIO.BCM)

GPIO.setup(18, GPIO.IN, pull_up_down=GPIO.PUD_UP)

while True:
    input_state = GPIO.input(18)
    if input_state == False:
        print('Button Pressed')
        time.sleep(0.2)

import RPi.GPIO as GPIO
import time

GPIO.setmode(GPIO.BCM)

GPIO.setup(23, GPIO.IN, pull_up_down=GPIO.PUD_UP)#Button to GPIO23
GPIO.setup(24, GPIO.OUT)  #LED to GPIO24

try:
    while True:
         button_state = GPIO.input(23)
         if button_state == False:
             GPIO.output(24, True)
             print('Button Pressed...')
             time.sleep(0.2)
         else:
             GPIO.output(24, False)
except:
    GPIO.cleanup()

## gpio zero

### LED

from gpiozero import LED
led = LED(17)
led.on()

### LED API

* led.on()
* led.off()
* led.toggle()
* led.blink()

### PIR

from gpiozero import MotionSensor
pir = MotionSensor(4)
while True:
 if pir.motion_detected:
 print("You moved")

### PIR API
* pir.wait_for_motion()
* pir.wait_for_no_motion()
* pir.motion_detected
* pir.when_motion = motor.forward
* pir.when_no_motion = motor.backward

### Moter

from gpiozero import Motor
motor = Motor(forward=17, backward=18)
motor.forward()

### Motor API

* motor.forward()
* motor.backward()
* motor.stop()
* motor.reverse()

### UART

import serial
import os
import time

port = "COM5"
Packet = 115200
ser = serial.Serial(port,Packet,timeout =1)

print(ser)      # print serial config

while True:
    
    ser.write("Hello".encode('utf-8'))
    time.sleep(1)
    print(ser.read(1).decode('utf-8'))
    time.sleep(1)

### HC-SR04

import RPi.GPIO as GPIO
import time
import signal
import sys

# use Raspberry Pi board pin numbers
GPIO.setmode(GPIO.BCM)

# set GPIO Pins
pinTrigger = 18
pinEcho = 24

# set GPIO input and output channels
GPIO.setup(pinTrigger, GPIO.OUT)
GPIO.setup(pinEcho, GPIO.IN)

def close(signal, frame):
    print("\nTurning off ultrasonic distance detection...\n")
    GPIO.cleanup() 
    sys.exit(0)

signal.signal(signal.SIGINT, close)

def main():

    while True:
        # set Trigger to HIGH
        GPIO.output(pinTrigger, True)
        # set Trigger after 0.01ms to LOW
        time.sleep(0.00001)
        GPIO.output(pinTrigger, False)

        startTime = time.time()
        stopTime = time.time()

		# save start time
        while 0 == GPIO.input(pinEcho):
            startTime = time.time()

		# save time of arrival
        while 1 == GPIO.input(pinEcho):
            stopTime = time.time()

		# time difference between start and arrival
        TimeElapsed = stopTime - startTime
		# multiply with the sonic speed (34300 cm/s)
		# and divide by 2, because there and back
        distance = (TimeElapsed * 34300) / 2

        #print ("Distance: %.1f cm" % distance)
        #time.sleep(1)
        if distance >=0 and distance <= 100:
           print("小")
           print ("Distance: %.1f cm" % distance)
           time.sleep(1)
        elif distance <=100 and distance >500:
           print("中")
           print ("Distance: %.1f cm" % distance)
           time.sleep(1)
        elif distance <=500 and distance >1000:
           print("大")
           print ("Distance: %.1f cm" % distance)
           time.sleep(1)
if __name__ == '__main__':
    main()