Send infrared commands from the Arduino to the iRobot Roomba. Use a transistor to drive the IR LED from pin D3 for maximal range.

Send infrared commands from the Arduino to the iRobot Roomba

#include <IRremote.h>

/*

 Send infrared commands from the Arduino to the iRobot Roomba
 by probono
 
 2013-03-17 Initial release
 
 Copyright (c) 2013 by probono
 All rights reserved.
 
 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions are met: 
 
 1. Redistributions of source code must retain the above copyright notice, this
 list of conditions and the following disclaimer. 
 2. Redistributions in binary form must reproduce the above copyright notice,
 this list of conditions and the following disclaimer in the documentation
 and/or other materials provided with the distribution. 
 
 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
 ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 IR Remote Control
 129 Left 
 130 Forward 
 131 Right 
 132 Spot 
 133 Max 
 134 Small 
 135 Medium 
 136 Large / Clean 
 137 Stop 
 138 Power 
 139 Arc Left 
 140 Arc Right 
 141 Stop  
 
 Scheduling Remote  
 142 Download 
 143 Seek Dock 
 
 Roomba Discovery Driveon Charger 
 240 Reserved 
 248 Red Buoy 
 244 Green Buoy 
 242 Force Field 
 252 Red Buoy and Green Buoy 
 250 Red Buoy and Force Field 
 246 Green Buoy and Force Field 
 254 Red Buoy, Green Buoy and Force 
 
 Roomba 500 Drive-on Charger
 160 Reserved 
 161 Force Field 
 164 Green Buoy 
 165 Green Buoy and Force Field 
 168 Red Buoy 
 169 Red Buoy and Force Field 
 172 Red Buoy and Green Buoy 
 173 Red Buoy, Green Buoy and Force Field
 
 Roomba 500 Virtual Wall
 162 Virtual Wall 
 
 Roomba 500 Virtual Wall Lighthouse ###### (FIXME: not yet supported here)
 0LLLL0BB 
 LLLL = Virtual Wall Lighthouse ID
 (assigned automatically by Roomba 
 560 and 570 robots) 
 1-10: Valid ID 
 11: Unbound 
 12-15: Reserved 
 BB = Which Beam
 00 = Fence 
 01 = Force Field 
 10 = Green Buoy 
 11 = Red Buoy
 
 */

IRsend irsend; // hardwired to pin 3; use a transistor to drive the IR LED for maximal range

void setup() 
{
  Serial.begin(9600); 
}

void loop() 
{
  // Read 3-digit code from serial line and send it via IR 
  char buffer[] = {
    ' ',' ',' '    }; // Receive up to 3 bytes
  while (!Serial.available()); // Wait for characters
  Serial.readBytesUntil('\n', buffer, 3);
  int incomingValue = atoi(buffer);
  if(incomingValue > 0) roomba_send(incomingValue); 
  delay(1000);
}

void roomba_send(int code) 
{
  Serial.print("Sending Roomba code ");
  Serial.print(code);
  int length = 8;
  unsigned int raw[length*2];
  unsigned int one_pulse = 3000;
  unsigned int one_break = 1000;
  unsigned int zero_pulse = one_break;
  unsigned int zero_break = one_pulse;

  int arrayposition = 0;
  // Serial.println("");
  for (int counter = length-1; counter >= 0; --counter) {
    if(code & (1<<counter)) {
      // Serial.print("1");
      raw[arrayposition] = one_pulse;
      raw[arrayposition+1] = one_break;
    } 
    else {
      // Serial.print("0");
      raw[arrayposition] = zero_pulse;
      raw[arrayposition+1] = zero_break;
    }
    arrayposition = arrayposition + 2;
  } 
  for (int i = 0; i < 3; i++) {
    irsend.sendRaw(raw, 15, 38);
    delay(50);
  }
  Serial.println("");

  /*
  Serial.print("Raw timings:");
   for (int z=0; z<length*2; z++) {
   Serial.print(" ");
   Serial.print(raw[z]);
   }
   Serial.print("\n\n");
   */
}