/*
 * DCT700 dual /Arduino IR blaster.
 * 
 * Copyright (c) 2009 Alex Williamson
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation, 59 Temple Place, Suite 330,
 * Boston, MA 02111-1307 USA
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * For the complete license, please see http://www.fsf.org/licenses/gpl.txt
 * or request a copy from the author of this program.
 */
 
 /* I modified this code to modulate at exactly 38khz and use two output pins to control two DCT700′s */

#include <util/delay.h>

/* From DCT700 remote lirc files, times in us */
#define PHEAD 9000
#define SHEAD 4400
#define PONE 550
#define SONE 4400
#define PZERO 550
#define SZERO 2150
#define PTRAIL 550
/* for some reason the DCT700 doesnt register a zero unless you send a repeat pulse after a delay ETRAIL is the delay */
#define ETRAIL 42050
#define GAP 11000

#define DATA_BITS 16
#define POST_BITS 0

#define PERIOD_US 27  // ~= (1/56kHz) * 1000000

#define DEFAULT_REMOTE 0×000
#define DEFAULT_REPEAT 0
#define DEFAULT_DELAY 250

int IR_PIN;
/*
 Changed this to digitalWrite and adjusted PERIOD_US by measuring frequency on OSCOPE
 */
 
static void modulate(int time)
{
int count = time / PERIOD_US;
        for(int i = 0; i <= count; i++) {
        digitalWrite(IR_PIN, HIGH);
        delayMicroseconds(10);
        digitalWrite(IR_PIN, LOW);
        delayMicroseconds(10);
        }

}

static void inline send_bit(int bit)
{
if (bit) {
               /* Serial.print(“1″);*/
modulate(PONE);
_delay_loop_2((SONE * 4) - 440);
} else {
              /* Serial.print(“0″); */
modulate(PZERO);
_delay_loop_2((SZERO * 4) - 250);
}
}

static byte inline wait_for_byte()
{
while (!Serial.available());
return Serial.read();
}

static void usage(void)
{
Serial.print(“Arduino dish IR blaster\n”);
Serial.print(“Default remote code: “);
Serial.print(DEFAULT_REMOTE, DEC);
Serial.print(“\nDefault repeat count: “);
Serial.print(DEFAULT_REPEAT, DEC);
Serial.print(“\nDefault post command delay: “);
Serial.print(DEFAULT_DELAY, DEC);
Serial.print(“(ms)\nCommand format: ”
     ”[#][@][d].\n");
Serial.print("Values in decimal\n");
}

} while (--repeat > 0);
Serial.print("\n");
delay(delay_ms);
}

This program needs you to key in the OBC codes (in the serial monitor). At first I was typing in the EFC codes that OFA remotes use. They won’t work here.

Here are the OBC codes for the more useful functions that don’t appear on any keys on your original Samsung TV remote:

Discrete ON 153
Discrete OFF 152
Component 1 134
Component 2 136
HDMI 1 233
HDMI 2 190
HDMI 3 194
PC 105
AV 1 133
AV 2 237

These worked on my model LN-Txx61F Samsung TV. Its device code was also 7 like the program has it, but yours might be different. You might run Lucas’ IRMON sketch to find out what it is.

I had luck programming my learning remote by transmitting the code just once (leaving CONTINUOUS undefined). YMMV. I’m not sure if Samsung complies with the special repeat code in the NEC protocol for when you hold down a key, but this program doesn’t do repeats the NEC way.

I also moved the IR LED from pin 13 to 2 so I could use a smaller resistor and get a more powerful signal. In the modulate() function, I used PORTD and a mask of 0×04 to control pin 2.

Note that the NEC protocol specifies that ON_START_TIME is 9000, but Samsung deviates from this and uses 4500.

Many thanks, Lucas.