Physical computing with Scratch and Python

Physical computing with Raspberry Pi using Scratch and Python with GPIO Zero

Transcript

1. Physical Computing
   with Scratch and Python
   

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3. Boot the Pi and open Scratch
   

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4. GPIO Server
   ●
   GPIO Server On
   

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5. Broadcast
   ●
   configXout
   ●
   gpioXon
   ●
   gpioXoff
   ●
   wait X secs
   ●
   forever
   Component GPIO pin
   Red LED 25
   Amber LED 8
   Green LED 7
   Buzzer 15
   

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6. Close Scratch and open Python 3
   

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7. Open a new file
   ●
   File > New File
   ●
   File > Save
   ●
   Save as camjam.py
   

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8. GPIO Zero LED
   from gpiozero import LED
   led = LED(25)
   while True:
   led.on()
   sleep(1)
   led.off()
   sleep(1)
   Save and run:
   Ctrl + S
   F5
   

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9. GPIO Zero LED
   from gpiozero import LED
   led = LED(25)
   led.blink()
   

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10. GPIO Zero Button + LED
    from gpiozero import Button, LED
    button = Button(21)
    led = LED(25)
    while True:
    button.wait_for_press()
    led.on()
    button.wait_for_release()
    led.off()
    

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11. GPIO Zero Button + LED
    from gpiozero import Button, LED
    button = Button(21)
    led = LED(25)
    while True:
    led.on()
    button.wait_for_press()
    led.off()
    button.wait_for_release()
    

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12. GPIO Zero Button + LED
    from gpiozero import Button, LED
    button = Button(21)
    led = LED(25)
    while True:
    led.blink()
    button.wait_for_press()
    led.off()
    button.wait_for_release()
    

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13. Traffic Lights
    from gpiozero import Button, TrafficLights
    button = Button(21)
    lights = TrafficLights(25, 8, 7)
    while True:
    button.wait_for_press()
    lights.on()
    button.wait_for_release()
    lights.off()
    

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14. Traffic Lights
    from gpiozero import Button, TrafficLights
    button = Button(21)
    lights = TrafficLights(25, 8, 7)
    while True:
    lights.blink()
    button.wait_for_press()
    lights.on()
    button.wait_for_release()
    

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15. Traffic Lights
    from gpiozero import Button, TrafficLights, Buzzer
    from time import sleep
    button = Button(21)
    lights = TrafficLights(25, 8, 7)
    buzzer = Buzzer(15)
    while True:
    lights.on()
    buzzer.off()
    button.wait_for_press()
    lights.off()
    buzzer.on()
    button.wait_for_release()
    

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16. Traffic Lights
    while True:
    lights.green.on()
    sleep(1)
    lights.amber.on()
    sleep(1)
    lights.red.on()
    sleep(1)
    lights.off()
    

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17. Traffic Lights
    while True:
    button.wait_for_press()
    lights.green.on()
    sleep(1)
    lights.amber.on()
    sleep(1)
    lights.red.on()
    sleep(1)
    lights.off()
    

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18. Traffic Lights Sequence
    ●
    Can you make a full traffic lights sequence?
    ●
    Use the button for a pedestrian crossing
    ●
    Use buzzer.beep() to indicate safe crossing
    

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19. Documentation and help guides
    ●
    raspberrypi.org/documentation/usage/scratch/gpio
    ●
    gpiozero.readthedocs.org
    ●
    raspberrypi.org/resources
    ●
    raspberrypi.org/education/downloads
    

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20. Physical Computing
    with Scratch and Python
    

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