Taking advantage of the OS

Since the BeagleBone is running a full GNU/Linux operating system, there are plenty of great tools available for us to take advantage of. Let's look at a couple of the advantages an OS gives you.

Multiprocessing

Every time you click on Run in Cloud9, it launches the program as a new process, so you can easily run many different programs simultaneously. Let's add a second transistor/LED circuit, this time using GPIO3_19 on P9.27.

For this, you will need:

• Breadboard

• 2x 5 mm LED

• 2x 4.7 kΩ resistor

• 2x 68 Ω resistor

• 2x 2N3904 NPN transistor

• Jumper wires

Wire it up on your breadboard as shown here:

Now create a new file called blink2.py, and this time, let's use PyBBIO, as shown in the following code:

from bbio import *

LED_PIN = GPIO3_19

def setup():
  pinMode(LED_PIN, OUTPUT)
 
def loop():
  digitalWrite(LED_PIN, HIGH)
  delay(250)
  digitalWrite(LED_PIN, LOW)
  delay(250)
   
run(setup, loop)

As you can see, this time, we're delaying the loop by 250 milliseconds or a quarter...