Physical computing with Scratch and Python

Transcript

1. Physical Computing with Scratch and Python

2. None

3. Boot the Pi and open Scratch

4. GPIO Server • GPIO Server On

5. Broadcast • configXout • gpioXon • gpioXoff • wait X

   secs • forever Component GPIO pin Red LED 25 Amber LED 8 Green LED 7 Buzzer 15

6. Close Scratch and open Python 3

7. Open a new file • File > New File •

   File > Save • Save as camjam.py

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

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

   led.blink()

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()

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()

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()

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()

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()

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()

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

    lights.off()

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()

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

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

    • raspberrypi.org/education/downloads

20. Physical Computing with Scratch and Python