binary-clock-workshop

These are the steps of the Building Binary Clock with Raspberry Pi Zeros Workshop

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Basic Hardware

During this lab, you will start attaching external hardware such as LEDs and controlling using the Python programming language.

Blink Wiring

Wire Up LED

Add LED (green) to breadboard with netative (shorter) leg in F30 and the positive (longer) leg in F29.
Add a short black wire connecting J30 to closest negative (-) row.
Ground the negative row by connecting a long black wire to the top negative (-) row hole around J1 to a Ground on the Raspberry Pi.
Add a color wire from J29 to GPIO 21.

Controlling LED

Start interactive Python shell.
```
python3
```

Initialize the LED GPIO.

import RPi.GPIO as GPIO
GPIO.setmode(GPIO.BCM)
GPIO.setup(21,GPIO.OUT)

Turn LED on.
```
GPIO.output(21, GPIO.HIGH)
```
Turn LED off.
```
GPIO.output(21, GPIO.LOW)
```
Import time library.
```
import time
```

Blink LED.

while True:
 GPIO.output(21, GPIO.HIGH)
 time.sleep(1)
 GPIO.output(21, GPIO.LOW)
 time.sleep(1)

NOTE: The while True creates an infinate loop for all code indentened after it.

Watch LED blink for a minute or so.
Ctrl+C to terminate loop.
Exit Python interactive shell.
```
exit()
```

Gpiozero Library

Having to manage the GPIO port can be a hastle in more complicated programs. The Gpiozero Python libary simplifies this.

Documentation: https://gpiozero.readthedocs.io/en/stable/

Controlling LED with Gpiozero

On the Raspberry Pi command-line, start interactive Python shell.
```
python3
```
Initialize the LED GPIO.
```
from gpiozero import LED
led = LED(21)
```
Turn LED on.
```
led.on()
```
Turn LED off.
```
led.off()
```
Blink LED.
```
led.blink()
```
Blink LED faster.
```
led.blink(.1, .1)
```
HINT: https://gpiozero.readthedocs.io/en/stable/api_output.html
Blink LED slowly 3 times.
```
led.blink(2, 2, 3)
```
Exit Python interactive shell.
```
exit()
```