I need to send a small amount of data over IrDA to a PDA. Any ideas? I have searched the forum, but been unable to find anything...
Just output your bytes to the +pin of your IR-led (very cheap) and the -pin to the GND.
Have you already written the data? That would mean you are done. You can send bytes using a serial connection
@masterens: what about modulation?
What abour IRDA protocols?
It dont know about IrDA protocols, but I know that modulation is harder to acomplish. Frequency Modulation is maybe even impossible, and Amplitude Modulation is actually what this is, but then in a great measure. You can just turn the led on and off, it is as simple as that. I did it myself before, with a bypass at my lamb.
You can just turn the led on and off, it is as simple as that.
But that won't get it into a PDA using IrDA, which is what the questioner is asking.
I did it myself before, with a bypass at my lamb.
???
This is a lamb:-
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This is a lamb:-
That it is....
My 2 cents:
For sending data over IR, try sending pulses that are different lengths. I forget where it was, but 600ms was a logical 0 and 700 ms was a logical 1. However, I am sure that you can use shorter times.
You would need an encoder, and a decoder, however. How does your PDA even recieve IR data?
@KnuttyD
How does your PDA even recieve IR data?
We know this, it uses the IrDA protocol. What the OP wants to know is how to implement this protocol on an arduno.
Do you know?
No neither do I, so please don't waste everyone's time with comments that are not relevant.
Here are some Vishay ICs for IrDA: http://www.mouser.com/Vishay/_/N-1z0zls5Zscv7Zlls6?Keyword=IrDA The data sheets explain their usage.
Here is a general description from Vishay: http://www.vishay.com/docs/82513/physical.pdf
I am doing the opposite. I am trying to read IrDA because I want to connect the Palm IR keyboard to my Arduino. The IrDA protocol is supposed to be very similar to 2400baud RS232 but the pulse widths are much faster to conserve battery. So the RS232 ports do not work. However, there is a virtual RS232 available which uses the
#include <SoftwareSerial.h> This allows you to assign TX RX to any data pin.
Arduino also has the ability to measure pulse widths with the Arduino pulseIn() command.
I think it's possible to write an IrDA protocol, and it might already exist. I'm still looking
Here is an article where the BASIC stamp was used to interface to IrDA using the MAX3100. IrDA with the BASIC Stamp and MAX3100
We could also use the MAX3100, but BASIC stamp does not have the ability to read pulse widths like we do with the pulseIn() command so I think we could read IrDA directly straight from an IR receiver like a DFrobot DFR0094 Digital IR Receiver Module without any translation hardware. Currently I am using a DFrobot DFR0094 Digital IR Receiver on RS232 pin 0 running this code and am picking up garbage characters because its not getting the information right from the narrow pulse widths of the IrDA protocol but I'm getting closer.
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
int i =0;
LiquidCrystal_I2C lcd(0x27,16,2); // set the LCD address to 0x27 for a 16 chars and 2 line display
void setup()
{
lcd.init(); // initialize the lcd
lcd.backlight();
Serial.begin(2400);
}
void loop()
{
// when characters arrive over the serial port...
if (Serial.available()) {
// wait a bit for the entire message to arrive
delay(100);
// clear the screen
lcd.clear();
// read all the available characters
while (Serial.available() > 0) {
// display each character to the LCD
lcd.write(Serial.read());
i++;
}
Serial.println();
Serial.print(i);
Serial.println(" Characters Sent");
i=0;
}
}