I took apart a asus eee pc remote control and borrowed it's ir sensor to implement the remote using my arduino. I have a sketch I borrowed from ladyada so I can look at the raw ir signal. Since she has a professional scope and I have a cheapo one who doesn't trigger properly. But I don't get the same results each time. I tested the sensor using the asus board without it's case and it works fine.

I noticed on the asus board it has some fitlering caps,100 ohm resistor and what looks like an inductor/fuse. Am assuming I shouldn't just wire the vcc = 5v gnd=gnd ouput = digital 2? How should I be wiring this up

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    \$\begingroup\$ I have a transistor, two resistors, 2 capacitors and a diode. How should I wire that up and will it work? BTW who is "ladyada" - my mother's called Ada FYI but she hasn't a scope. \$\endgroup\$ – Andy aka Apr 16 '14 at 9:30
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    \$\begingroup\$ @Andyaka What? Your mother isn't ladyaka? \$\endgroup\$ – gwideman Apr 16 '14 at 11:19
  • \$\begingroup\$ @Andyaka Ladyada is a nickname for Limor Fried, founder of Adafruit.com, a popular source of electronics parts for hobbyists. \$\endgroup\$ – JYelton Apr 16 '14 at 17:37

So apparently you're following the article here: https://learn.adafruit.com/ir-sensor/using-an-ir-sensor. This is a TSOP382xx (http://www.adafruit.com/datasheets/tsop382.pdf), which is not merely an IR sensor. It includes internal circuitry that detects 38kHz signals, and demodulates them.

To clarify a little, on page https://learn.adafruit.com/ir-sensor/ir-remote-signals , the narrative talks about using a basic IR photodetector (photodiode or phototransistor), with no additional logic, to view the 'raw" 38 kHz pulses (25 microsecond cycles) of IR on a scope. This exercise shows the blocks of pulses which form the form the ones and zeroes (lengths in the low millisecond range) of the message.

At the end of that page, the narrative switches to the PNA4602 for use with the Arduino. The PNA4602 digests the blocks of 38kHz pulses, and turns it into simple ones and zeros of low millisec duration, a pace that the Arduino can keep up with.

Very distractingly, the "Raw IR decoder sketch!" on page https://learn.adafruit.com/ir-sensor/using-an-ir-sensor does NOT deal with the same level of "rawness" as on the previous page. It deals with output from the PNA4602. It is only "raw" in the sense that the sketch reads the millisec-rate bits, and outputs their lengths in millisecs, rather than reading entire bytes or interpreting the stream into a message.

The sensor you want to pull from your Asus might be similar, or it might be just an IR phototransistor or diode, to be used with separate 38kHz demodulation circuitry.

You'll need to either find a part number on that Asus part and look it up, or do some breadboard tests to determine what it is.

Or send ladyada $1.95 and get the one in the article, already figured out. :-)

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  • \$\begingroup\$ Thanks for the help. It appears The IRemote library is able to consistently deal with my remote. \$\endgroup\$ – Ageis Apr 19 '14 at 0:27

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