Remote Control - Unable to send command to TV

Other Hardware Sensors
1

Hi All

I am trying the IR Library from Ken Shirriff's blog: arduino - the GITHUB Version

I am using an Arduino Duemilanove

I have an IR Receiver and it has picked up the TV as using a NEC code - The TV is a Sharp.

The code to turn the TV on is 2FD48B7 and the capture sketch says it is 32 bits.

So I am trying to send this back to the TV from Arduino

The IRRecvDUMP sketch produces this output

Decoded NEC: 2FD48B7 (32 bits)
Raw (68): 7026, 8950, -4450, 550, -550, 600, -500, 600, -550, 550, -550, 600, -550, 550, -550, 550, -1650, 600, -550, 550, -1650, 550, -1650, 600, -1600, 600, -1650, 550, -1650, 550, -1650, 600, -500, 600, -1650, 550, -550, 600, -1600, 600, -550, 550, -550, 600, -1600, 600, -550, 550, -550, 600, -550, 550, -1650, 550, -550, 600, -1600, 600, -1650, 550, -550, 600, -1600, 600, -1650, 550, -1650, 550

I have Pin 3 to 100ohm Resister to IP Transmitter (long leg), (short leg) to ground.

I can see the IR resister light up if I use a Cell Phone to look at the sensor.

My sketch

/*

  • IRremote: IRsendDemo - demonstrates sending IR codes with IRsend
  • An IR LED must be connected to Arduino PWM pin 3.
  • Version 0.1 July, 2009
  • Copyright 2009 Ken Shirriff
  • http://arcfn.com
    */

#include <IRremote.h>

IRsend irsend;

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

void loop() {
if (Serial.read() != -1) {
for (int i = 0; i < 3; i++) {
irsend.sendNEC(0x2FD48B7, 32);
delay(40);

}
Serial.print("Done...");
}
}

So I send a keypress in serial monitor and it sends the NEC code to the TV but nothing happens.

I do not know how to trouble shoot this.

chris
=(

2

Did you get the IR LED close to the TV? A high-power IR LED will need 100 mA for full brightness. The Arduino will supply 40 at most and less with a current dropping resistor. What are the characteristics (forward voltage drop and recommended current) of your LED?

3

johnwasser:
Did you get the IR LED close to the TV? A high-power IR LED will need 100 mA for full brightness. The Arduino will supply 40 at most and less with a current dropping resistor. What are the characteristics (forward voltage drop and recommended current) of your LED?

The IR Sensor I am using is here - not a lot of detail but some.

5mm Infrared Transmitting LED

5MM EMITTING DIODELooks like a 5mm LED & has a blue transparent lens.

Specifications:-
Forward Current (If): 50mA max
Peak forward current (Ip): 1.2A
Forward Voltage (VF): 1.2V @ 20mA
Reverse Voltage (VR): 5V max
Power Dissipation (Pd): 100mW max
Viewing Angle: 30°
Peak Spectral Wavelength(IR): 940nm @ 20mA * Spectral Bandwidth (DI): 50nm@20mA
Material: GaAs

http://jaycar.com.au/productView.asp?ID=ZD1945&keywords=ZD-1945&form=KEYWORD

I removed the resister and moved the unit closer to the TV about 8" and it worked!!!

So output power is an issue and I am a super newbee to electronics - interesting how all the remote control examples with Arduino never mentioned what you said in 2 lines!!!

If you can give me any more ideas on how to implement a higher power output that would be appreciated.

Chris

4

johnwasser:
Did you get the IR LED close to the TV? A high-power IR LED will need 100 mA for full brightness. The Arduino will supply 40 at most and less with a current dropping resistor. What are the characteristics (forward voltage drop and recommended current) of your LED?

Would you suggest a small circuit outside of arduino to give enough power to the IR LED?

Maybe the Arduino controls an OptoIsolator - the isolator is connected to 5v and with a 100ohm resisiter would give 50ma to the IR LED?

Is this the right way to be thinking?

I do not want to control my TV at the end of the day but a HEAT PUMP (Air Con)

Chris