IRForum

Wow, great bit of Arduino coding with your https://www.analysir.com/blog/2014/05/2 ... eceiver-2/ project. I got it working and just had a couple of comments/questions:

• I think there's a typo in sketch. This line refers to pin 2 but pin 0 is being used just after the open bracket:

  Code: Select all

  //default definition for ISR
  #define enableIRrx attachInterrupt(0, rxIR_Interrupt_Handler, FALLING) //set up interrupt handler for IR rx   on pin 2 - demodulated signal
  

• You may want to mention that the serial monitor baud should be set to 115200, to match your Arduino sketch serial setting.
• I happened to have a photodiode with the black coating to filter most non-IR wavelengths and it works a lot better than the clear emitter. I ended up getting a range of 50cm using TV remote with new batteries!
• In the blog you state "this software will just report the signal timings on the serial port" - but when I look at the output, some results are negative and some really large. Can you explain what the numbers mean (example below)?
• Any idea how I'd convert the output into a HEX code?

Here's what I get after pressing "1" on TV remote three times:

, +2308548516, +2308546340, +60, -1720, +4294965576, -2556, +44, -0, +64, -0, +4294967020, -300, +4294966996, -304, +4294966992, -292, +4294967004, -292, +4294967004, -304, +4294966992, -812, +52, -292, +4294967004, -812, +44, -1712, +36, -284, +4294967012, -848, +24, -276, +20, -272, +40, -300, +4294966996, -296, +4294967000, -1148, +4294966148, -280, +4294967016, -276, +4294967020, -540, +20, -300, +40, -296, +4294967000, -836, +48, -288, +4294967008, -840, +4294967000, -1696, +36, -816, +48, -316, +4294966980, -832, +4294967000, -828, +32, -816, +4294966988, -1728, +32, -828, +40, -816, +52, -1700, +52, -77644, +4294889652, -79816, +4294887480, -0, +40, -1684, +52, -0, +4294967008, -288, +4294967008, -316, +4294966980, -284, +24, -528, +28, -832, +36, -832, +32, -0, +4294966988, -816, +36, -832, +32, -820, +4294966996, -832, +48, -1684, +36, -812, +44, -824, +52, -816, +56, -292, +4294967004, -280, +44, -544, +4294966752, -832, +32, -1700, +36, -0, +4294966992, -856, +20, -804, +60, -292, +4294967004, -824, +44, -860, +20, -284, +4294967012, -848, +24, -304, +36, -840, +24, -1700, +36, -0, +4294966992, -300, +40, -844, +20, -288, +4294967008, -292, +4294967004, -832, +40, -1712, +4294967000, -828, +36, -1188, +4294966108, -170036
Modulation Period: 16500 (nano seconds)
Modulation Frequency: 60606 (Hz)

, +2307040684, +2307038508, +44, -1732, +4294965564, -2564, +44, -832, +24, -0, +4294967004, -292, +4294967004, -836, +24, -824, +56, -0, +4294967012, -820, +28, -816, +48, -836, +32, -508, +32, -292, +48, -848, +4294966448, -2536, +52, -292, +4294967004, -288, +52, -296, +4294967000, -828, +48, -832, +24, -304, +4294966992, -840, +24, -272, +20, -292, +4294967004, -824, +28, -284, +4294967012, -820, +48, -300, +4294966996, -836, +44, -804, +48, -288, +4294967008, -800, +52, -1732, +4294965564, -816, +48, -292, +4294967004, -844, +4294966988, -832, +4294967008, -1700, +24, -828, +40, -836, +4294966996, -1684, +40, -0, +32, -77668, +4294889628, -79844, +4294887452, -80708, +4294886588, -308, +4294966988, -816, +36, -840, +52, -0, +4294967000, -824, +32, -852, +20, -832, +32, -0, +40, -288, +4294967008, -812, +44, -844, +36, -828, +24, -828, +48, -1164, +4294966132, -836, +28, -296, +4294967000, -816, +60, -304, +4294966992, -832, +40, -288, +4294967008, -1176, +4294966120, -824, +52, -832, +24, -292, +4294967004, -296, +44, -308, +4294966988, -832, +36, -816, +48, -304, +4294966992, -828, +44, -1168, +4294966128, -312, +4294966984, -856, +24, -804, +44, -304, +4294966992, -832, +40, -1168, +20, -304, +4294966992, -820, +48, -1172, +4294966124, -171220
Modulation Period: 16937 (nano seconds)
Modulation Frequency: 59042 (Hz)

, +2305832356, +2305830184, +44, -1732, +4294965564, -2564, +44, -828, +40, -0, +4294966996, -812, +52, -808, +60, -832, +36, -812, +52, -800, +68, -0, +4294966992, -304, +4294966992, -864, +4294966432, -828, +4294966992, -1684, +40, -856, +4294966440, -804, +4294967008, -832, +4294966464, -308, +4294966988, -812, +44, -0, +32, -1176, +36, -304, +28, -296, +4294967000, -300, +4294966996, -296, +4294967000, -836, +36, -832, +32, -816, +48, -1176, +4294966120, -820, +60, -1156, +48, -800, +4294967004, -288, +4294967008, -1668, +48, -292, +4294967004, -852, +28, -1168, +4294966128, -828, +52, -0, +64, -1144, +4294966152, -0, +40, -77668, +4294889628, -79840, +4294887456, -80704, +4294886592, -308, +4294966988, -816, +36, -840, +52, -0, +4294967000, -824, +32, -852, +20, -832, +32, -0, +28, -288, +4294967008, -812, +44, -844, +36, -828, +24, -828, +48, -1160, +4294966136, -840, +28, -296, +4294967000, -816, +60, -304, +4294966992, -832, +40, -304, +4294966992, -1164, +4294966132, -824, +52, -832, +24, -292, +4294967004, -296, +44, -308, +4294966988, -832, +36, -816, +48, -304, +4294966992, -828, +44, -1164, +4294966132, -312, +4294966984, -856, +44, -804, +44, -828, +52, -320, +4294966976, -832, +40, -304, +4294966992, -820, +48, -1164, +4294966132, -168448
Modulation Period: 27625 (nano seconds)
Modulation Frequency: 36199 (Hz)

Thanks!

The '0' here refers to INT0, which is exposed on pin 2 on arduinos (UNO etc).
There is a more recent function to make this portable, but wasn't common at the time of the original post.
This would be the updated version....but both will work OK.


If you changed that to 2 or connected to pin 0, it may explain your weird output!.....let me know.

Also, the 50CM range seems too far......it really needsto be up-close!
However, a photo-diode may work better than an IR emitter/LED. The target in this post was an IR emitter, as it is more common to have available than a photo-diode.
FYI: IR LEDs can also come with inbuilt filters, depending on model.

If you continue to have issues, post a photo of your setup including how you use the remote.

Thanks for the speedy response! Attached is a picture of my setup. FYI, I had to use a couple of 10k ohm resistors in parallel to make a 5k and a couple of 10ks in series to make 20k.

Regarding INT0 = pin 2, it all makes sense now. Looks like I'd only changed the #define enablelRrx under "//default definition for ISR" which coincided with output appearing on the serial monitor for the first time - but it was probably because of some other change I'd made. I'd forgotten about the test for ArduinoUno further in the code which re-asserts INT0: Strange results above might be because of the IR receiver diode I used. When I switched back to an IR emitter diode, I had to hold it less than 1cm from the emitter, and when pressing 1 on the TV remote twice, I now get:

, +80, -80, +4294967216, -728, +4294966568, -2460, +56, -812, +28, -1020, +4294966276, -1836, +28, -100, +4294967196, -920, +48, -680, +4294966616, -1548, +52, -868, +28, -784, +108, -864, +4294966432, -1732, +48, -80, +56, -0, +4294967216, -860, +4294964916, -2436, +132, -0, +4294965724, -820, +4294966476, -2468, +4294964828, -3332, +28, -188, +4294966588, -788, +4294966508, -76, +24, -920, +4294966536, -844, +4294966560, -56, +28, -0, +4294966512, -2540, +24, -868, +4294966428, -144, +4294966424, -1768, +4294965528, -2660, +4294964636, -708, +56, -56, +4294966456, -976, +48, -0, +28, -80, +4294967216, -56, +24, -4992, +4294962304, -5912, +4294961384, -7772, +4294959524, -8508, +52, -0, +4294966484, -1652, +4294965644, -4224, +28, -916, +4294966380, -1732, +48, -1736, +4294963040, -4308, +28, -784, +4294966512, -1648, +4294965648, -2516, +52, -868, +24, -25444294964752
Modulation Period: 2549125 (nano seconds)
Modulation Frequency: 392 (Hz)

, +164, -136, +4294967216, -136, +4294967160, -160, +28, -84, +48, -548, +4294967080, -156, +4294966460, -1052, +4294966244, -1944, +48, -0, +116, -148, +4294967148, -240, +4294967240, -840, +4294966456, -704, +4294966592, -0, +24, -268, +4294967164, -188, +28, -208, +4294967244, -1104, +52, -56, +4294966616, -212, +60, -212, +4294967084, -56, +4294967240, -52, +4294967244, -840, +4294966456, -56, +52, -212, +4294967244, -576, +24, -52, +4294967244, -1736, +4294964964, -2520, +4294967200, -888, +24, -132, +4294966540, -972, +32, -52, +4294967244, -108, +28, -0, +76, -108, +28, -240, +24, -1056, +4294966320, -244, +4294967104, -0, +4294967052, -52, +28, -52, +28, -0, +80, -728, +4294966752, -0, +28, -80, +4294967216, -864, +4294966432, -1784, +4294964700, -0, +24, -840, +48, -820, +72, -656, +4294965720, -1632, +28, -1784, +4294965512, -3484, +4294963812, -240, +4294967056, -184, +4294967112, -0, +24, -80, +4294967216, -1648, +4294965648, -2516, +4294964780, -104, +4294967192, -0, +4294966404, -80, +4294965568, -1780, +4294965516, -0, +28, -80, +4294967216, -868, +4294966400, -1760, +4294965536, -52, +48, -164, +4294967132, -972, +4294966324, -1840, +4294965456, -3540, +4294963756, -5224, +4294961260, -0, +4294961208, -184, +4294967112, -736, +4294966560, -524294967244
Modulation Period: 58375 (nano seconds)
Modulation Frequency: 17130 (Hz)

Sorry about the delay....

The sensor in the photo looks like a photo diode and not an IR LED.

As I mentioned, the circuit is designed to work with an IR LED emitter (not a photo sensor).

Also, please check that the LED is connected with correct polarity and also check it with the diode tester on a DMM, if available.