How to implement a keyboard using Arduino UNO?

Projects General Guidance
1

I was trying to read an IR remote signal using Arduino UNO.
The idea is to create a Wireless PowerPoint Slide Changer.
The keyboard functions required for this purpose, I found, won't work with UNO!
Is there any way out of it besides purchasing an Arduino Micro?

2

Yes, but they would be far more complex and more expensive than using a Micro (or Leonardo).

3

PaulRB:
Yes, but they would be far more complex and more expensive than using a Micro (or Leonardo).

Ok but what exactly is the alternative?

4

Actually, the UNO is perfectly able to function as a HID by reprogramming the ATmega8U2 USB interface chip. That is the exact reason for the design.

This may help.

5

Thank You so much :slight_smile:

6

Ok so I tested everything up and its working...but just the LEDs !!

Code is working fine, don't know what scan codes to send to computer !
Used this http://www.computer-engineering.org/ps2keyboard/scancodes2.html list but nothing working :~

7

What is wrong with this code?

#include <IRremote.h>

//initializing the pin
int recv_pin = 2;
int led = 13;

//Defining hex values for keyboard
const byte MAKE = 0xE0;
const byte BREAK = 0xF0;
const byte RightArrow = 0x74;
const byte LeftArrow = 0x6B;

//Defining pre-read IR remote key data
const long RIGHT_ARROW_DEC = 2160034684;
const long LEFT_ARROW_DEC = 2160040294;

//Class performing the decoding function
IRrecv irrecv(recv_pin);

//Decoding the results
decode_results results;

void setup()
{
  Serial.begin(9600);
  pinMode(led, OUTPUT);
  
  //Enabling the IR Receiver
  irrecv.enableIRIn();
}

void loop()
{
  //Checking if any value received
  if(irrecv.decode(&results))
  {
    //Printing the HEX value of the IR signal received
    Serial.println(results.value, DEC);
  
        //Checking which key is pressed and taking desired action
        if(results.value == RIGHT_ARROW_DEC)
          {
            glowLed();
            makeKey(MAKE, RA);
            breakKey(MAKE, BREAK, RA);
          }
        else if(results.value == LEFT_ARROW_DEC)
          {
            glowLed();
            makeKey(MAKE, LA);
            breakKey(MAKE, BREAK, LA);
          }
        //Preparing the receiver for next signal
         irrecv.resume();
     }
}

void glowLed()
{
     digitalWrite(led, HIGH);
     delay(20);
     digitalWrite(led, LOW);
     delay(20); 
}

void makeKey(byte val1, byte val2)
{
      Serial.write(val1);
      Serial.write(val2);
}

void breakKey(byte val1, byte val2, byte val3)
{
      Serial.write(val1);
      Serial.write(val2);
      Serial.write(val3);
}
8

The long constants should have an "L" after them?

9

Thanks PaulRB

Although I hadn't used that 'L' before, the LED was (is) blinking. No problem there.
The problem I am facing right now is the keyboard simulation.
Dunno why my makeKey() and breakKey() aren't working !!

10

ok so after some intense lookup i edited my code to this:

#include <ps2dev.h> //Library to emulate keyboard
#include "Arduino.h"
#include <IRremote.h>

PS2dev keyboard(3,2);  // PS2dev object (2:data, 3:clock)

//initializing the pin
int recv_pin = 2;
int led = 13;

//Defining hex values for keyboard
//const byte MAKE = 0xE0;
//const byte BREAK = 0xF0;
//const byte RA = 0x74;
//const byte LA = 0x6B;

//Defining pre-read IR remote key data
const long RIGHT_ARROW_DEC = 2160034684;
const long LEFT_ARROW_DEC = 2160040294;

//Class performing the decoding function
IRrecv irrecv(recv_pin);

//Decoding the results
decode_results results;

void setup()
{
  Serial.begin(9600);
  pinMode(led, OUTPUT);
  
  //Enabling the IR Receiver
  irrecv.enableIRIn();
}

void loop()
{
  //Checking if any value received
  if(irrecv.decode(&results))
  {
    //Printing the HEX value of the IR signal received
    //Serial.println(results.value, DEC);
  
        //Checking which key is pressed and taking desired action
        if(results.value == RIGHT_ARROW_DEC)
          {
            glowLed();
            keyboard.write(0xE0);
            keyboard.write(0x74);
            keyboard.write(0xE0);
            keyboard.write(0xF0);
            keyboard.write(0x74);
          }
        else if(results.value == LEFT_ARROW_DEC)
          {
            glowLed();
            keyboard.write(0xE0);
            keyboard.write(0x6B);
            keyboard.write(0xE0);
            keyboard.write(0xF0);
            keyboard.write(0x6B);
          }
        //Preparing the receiver for next signal
        delay(500);
         irrecv.resume();
     }
}

void glowLed()
{
     digitalWrite(led, HIGH);
     delay(20);
     digitalWrite(led, LOW);
     delay(20); 
}

and yes i have deleted the line #include "Wconstants.h" and replaced it with #include "Arduino.h"

Still no success =(