Userspace Arduino:BlinkUserspace

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Introduction

This is the most basic example for the Userspace Arduino library involving blinking an LED from a sketch. For the Beaglebone Black, the current variant has a setup as shown in the diagram.

Connecting an LED to the Beaglebone Black


Hardware

You need:

  • LED: any color and size. 10mm works fine
  • Resistor: > 470Ω to avoid exceeding the current limit of 4 mA per pin
  • Wire to join the stuff

Wire the LED with the positive (longer) end to P8_19 and the other end to GND.

Sketch

Derived from Blink

/*
  Blink
  Turns on an LED on for one second, then off for one second, repeatedly.
 
  This example code is in the public domain.
 */
 
// Pin 8_19 has an LED connected to it. It maps to 7 on the Beaglebone Black variant
// give it a name:
int led = 7;

// the setup routine runs once when you press reset:
void setup() {                
  // initialize the digital pin as an output.
  pinMode(led, OUTPUT);     
}

// the loop routine runs over and over again forever:
void loop() {
  digitalWrite(led, HIGH);   // turn the LED on (HIGH is the voltage level)
  delay(1000);               // wait for a second
  digitalWrite(led, LOW);    // turn the LED off by making the voltage LOW
  delay(1000);               // wait for a second
}