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3.1.2 Welcome
===============

Introduction
-------------

In this project, we will use PIR to sense the movement of pedestrians,
and use servos, LED, buzzer to simulate the work of the sensor door of
the convenience store. When the pedestrian appears within the sensing
range of the PIR, the indicator light will be on, the door will be
opened, and the buzzer will play the opening bell.

Components
---------------

.. image:: img/list_Welcome.png
    :align: center

Schematic Diagram
-------------------

============ ======== ======== ===
T-Board Name physical wiringPi BCM
GPIO18       Pin 12   1        18
GPIO17       Pin 11   0        17
GPIO27       Pin 13   2        27
GPIO22       Pin 15   3        22
============ ======== ======== ===

.. image:: img/Schematic_three_one2.png
   :align: center

Experimental Procedures
-------------------------

**Step 1:** Build the circuit.

.. image:: img/image239.png
    :width: 800
    :align: center

**For C Language Users**
^^^^^^^^^^^^^^^^^^^^^^^^^^

**Step 2:** Change directory.

.. raw:: html

   <run></run>

.. code-block:: 

    cd ~/davinci-kit-for-raspberry-pi/c/3.1.2/

**Step 3:** Compile.

.. raw:: html

   <run></run>

.. code-block:: 

    gcc 3.1.2_Welcome.c -lwiringPi

**Step 4:** Run.

.. raw:: html

   <run></run>

.. code-block:: 

    sudo ./a.out

After the code runs, if the PIR sensor detects someone passing by, the
door will automatically open (simulated by the servo), turn on the
indicator and play the doorbell music. After the doorbell music plays,
the system will automatically close the door and turn off the indicator
light, waiting for the next time someone passes by.

There are two potentiometers on
the PIR module: one is to adjust sensitivity and the other is to adjust
the detection distance. To make the PIR module work better, you
You need to turn both of them counterclockwise to the end.

.. note::

    If it does not work after running, or there is an error prompt: \"wiringPi.h: No such file or directory\", please refer to :ref:`C code is not working?`.

**Code Explanation**

.. code-block:: c

    void setAngle(int pin, int angle){    //Create a funtion to control the angle of the servo.
        if(angle < 0)
            angle = 0;
        if(angle > 180)
            angle = 180;
        softPwmWrite(pin,Map(angle, 0, 180, 5, 25));   
    } 

Create a function, setAngle to write the angle in the servo that is
0-180.

.. code-block:: c

    void doorbell(){
    for(int i=0;i<sizeof(song)/4;i++){
            softToneWrite(BuzPin, song[i]); 
            delay(beat[i] * 250);
        }

Create a function, doorbell to enable the buzzer to play music.

.. code-block:: c

    void closedoor(){
    digitalWrite(ledPin, LOW);   //led off
    for(int i=180;i>-1;i--){  //make servo rotate from maximum angle to minimum angle
        setAngle(servoPin,i);
        delay(1);
        }
    }

Create a closedoor function to simulate closing the door, turn off the
LED and let the servo turn from 180 degrees to 0 degree.

.. code-block:: c

    void opendoor(){
        digitalWrite(ledPin, HIGH);   //led on
        for(int i=0;i<181;i++){  //make servo rotate from minimum angle to maximum angle
            setAngle(servoPin,i);
            delay(1);
        }
        doorbell();
        closedoor();
    }

The function opendoor() includes several parts: turn on the indicator
light, turn the servo (simulate the action of opening the door), play
the doorbell music of the convenience store, and call the function
closedoor() after playing music.

.. code-block:: c

        int main(void)
    {
        if(wiringPiSetup() == -1){ //when initialize wiring failed,print message to screen
            printf("setup wiringPi failed !");
            return 1;
        }
        if(softToneCreate(BuzPin) == -1){
            printf("setup softTone failed !");
            return 1;
    ......

In the function main(), initialize library wiringPi and setup softTone,
then set ledPin to output state and pirPin to input state. If the PIR
sensor detects someone passing by, the function opendoor will be called
to simulate opening the door.



**For Python Language Users**
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

**Step 2:** Change directory.

.. raw:: html

   <run></run>

.. code-block::

    cd ~/davinci-kit-for-raspberry-pi/python/

**Step 3:** Run.

.. raw:: html

   <run></run>

.. code-block::

    sudo python3 3.1.2_Welcome.py

After the code runs, if the PIR sensor detects someone passing by, the
door will automatically open (simulated by the servo), turn on the
indicator and play the doorbell music. After the doorbell music plays,
the system will automatically close the door and turn off the indicator
light, waiting for the next time someone passes by.

There are two potentiometers on
the PIR module: one is to adjust sensitivity and the other is to adjust
the detection distance. To make the PIR module work better, you
You need to turn both of them counterclockwise to the end.

**code**

.. note::

    You can **Modify/Reset/Copy/Run/Stop** the code below. But before that, you need to go to  source code path like ``davinci-kit-for-raspberry-pi/python``. 
    
.. raw:: html

    <run></run>

.. code-block:: python

    import RPi.GPIO as GPIO
    import time

    SERVO_MIN_PULSE = 500
    SERVO_MAX_PULSE = 2500

    ledPin = 18    # define the ledPin
    pirPin = 17    # define the sensorPin
    servoPin = 22  # define the servoPin
    buzPin = 27    # define the buzzerpin


    CL = [0, 131, 147, 165, 175, 196, 211, 248]        # Frequency of Low C notes

    CM = [0, 262, 294, 330, 350, 393, 441, 495]        # Frequency of Middle C notes

    CH = [0, 525, 589, 661, 700, 786, 882, 990]        # Frequency of High C notes

    song = [    CH[5],CH[2],CM[6],CH[2],CH[3],CH[6],CH[3],CH[5],CH[3],CM[6],CH[2]    ]

    beat = [    1,1,1,1,1,2,1,1,1,1,1,]


    def setup():
        global p
        global Buzz                        # Assign a global variable to replace GPIO.PWM 
        GPIO.setmode(GPIO.BCM)       # Numbers GPIOs by physical location
        GPIO.setup(ledPin, GPIO.OUT)   # Set ledPin's mode is output
        GPIO.setup(pirPin, GPIO.IN)    # Set sensorPin's mode is input
        GPIO.setup(servoPin, GPIO.OUT)   # Set servoPin's mode is output
        GPIO.output(servoPin, GPIO.LOW)  # Set servoPin to low
        GPIO.setup(buzPin, GPIO.OUT)    # Set pins' mode is output

        Buzz = GPIO.PWM(buzPin, 440)    # 440 is initial frequency.
        Buzz.start(50)                    # Start Buzzer pin with 50% duty ration

        p = GPIO.PWM(servoPin, 50)     # set Frequece to 50Hz
        p.start(0)                     # Duty Cycle = 0

    def map(value, inMin, inMax, outMin, outMax):
        return (outMax - outMin) * (value - inMin) / (inMax - inMin) + outMin

        
    def setAngle(angle):      # make the servo rotate to specific angle (0-180 degrees) 
        angle = max(0, min(180, angle))
        pulse_width = map(angle, 0, 180, SERVO_MIN_PULSE, SERVO_MAX_PULSE)
        pwm = map(pulse_width, 0, 20000, 0, 100)
        p.ChangeDutyCycle(pwm)#map the angle to duty cycle and output it
        
    def doorbell():
        for i in range(1, len(song)):        # Play song 1
            Buzz.ChangeFrequency(song[i])    # Change the frequency along the song note
            time.sleep(beat[i] * 0.25)        # delay a note for beat * 0.25s
        time.sleep(1)                        # Wait a second for next song.

    def closedoor():
        GPIO.output(ledPin, GPIO.LOW)
        for i in range(180, -1, -1): #make servo rotate from 180 to 0 deg
            setAngle(i)
            time.sleep(0.001)
        time.sleep(1)
    def opendoor():
        GPIO.output(ledPin, GPIO.LOW)
        for i in range(0, 181, 1):   #make servo rotate from 0 to 180 deg
            setAngle(i)     # Write to servo
            time.sleep(0.001)
        time.sleep(1)
        doorbell()
        closedoor()

    def loop():
        while True:
            if GPIO.input(pirPin)==GPIO.HIGH:
                opendoor()


    def destroy():
        GPIO.cleanup()                     # Release resource
        p.stop()
        Buzz.stop()

    if __name__ == '__main__':     # Program start from here
        setup()
        try:
            loop()
        except KeyboardInterrupt:  # When 'Ctrl+C' is pressed, the program destroy() will be  executed.
            destroy()

**Code Explanation**

.. code-block:: python

    def setup():
        global p
        global Buzz                        # Assign a global variable to replace GPIO.PWM
        GPIO.setmode(GPIO.BCM)       # Numbers GPIOs by physical location
        GPIO.setup(ledPin, GPIO.OUT)   # Set ledPin's mode is output
        GPIO.setup(pirPin, GPIO.IN)    # Set sensorPin's mode is input
        GPIO.setup(buzPin, GPIO.OUT)    # Set pins' mode is output
        Buzz = GPIO.PWM(buzPin, 440)    # 440 is initial frequency.
        Buzz.start(50)                    # Start Buzzer pin with 50% duty ration
        GPIO.setup(servoPin, GPIO.OUT)   # Set servoPin's mode is output
        GPIO.output(servoPin, GPIO.LOW)  # Set servoPin to low
        p = GPIO.PWM(servoPin, 50)     # set Frequece to 50Hz
        p.start(0)                     # Duty Cycle = 0

These statements are used to initialize the pins of each component.

.. code-block:: python

    def setAngle(angle):      # make the servo rotate to specific angle (0-180 degrees) 
        angle = max(0, min(180, angle))
        pulse_width = map(angle, 0, 180, SERVO_MIN_PULSE, SERVO_MAX_PULSE)
        pwm = map(pulse_width, 0, 20000, 0, 100)
        p.ChangeDutyCycle(pwm)#map the angle to duty cycle and output it

Create a function, servowrite to write the angle in the servo that is
0-180.

.. code-block:: python

    def doorbell():
        for i in range(1,len(song)): # Play song1
            Buzz.ChangeFrequency(song[i]) # Change the frequency along the song note
            time.sleep(beat[i] * 0.25) # delay a note for beat * 0.25s

Create a function, doorbell to enable the buzzer to play music. 

.. code-block:: python

    def closedoor():
        GPIO.output(ledPin, GPIO.LOW)
        Buzz.ChangeFrequency(1)
        for i in range(180, -1, -1): #make servo rotate from 180 to 0 deg
            setAngle(i)
            time.sleep(0.001)

Close the door and turn off the indicator light.

.. code-block:: python

    def opendoor():
        GPIO.output(ledPin, GPIO.LOW)
        for i in range(0, 181, 1):   #make servo rotate from 0 to 180 deg
            setAngle(i)     # Write to servo
            time.sleep(0.001)
        doorbell()
        closedoor()

The function, opendoor() consists of several parts: turn on the
indicator light, turn the servo (to simulate the action of opening the
door), play the doorbell music of the convenience store, and call the
function , closedoor() after playing music.

.. code-block:: python

    def loop():
    while True:
        if GPIO.input(pirPin)==GPIO.HIGH:
            opendoor()

When PIR senses that someone is passing by, it calls the function,
opendoor().

Phenomenon Picture
--------------------

.. image:: img/image240.jpeg
   :align: center