amc2011,
thanks for coming clean! MANY of us would like to have the time to afford going back and redoing some of our first projects!

You'll find that this crowd, at least after all this explanation and hand-wringing, will gladly accept a less than polished code.

Maybe you two are onto something that we just haven't opened our eyes to. Sometimes when my clients say they have what might be a stupid suggestion, I tell them "Well, I know how to do it," and while I'm saying that, I put my hands up to the sides of my face to show that I know I have blinders on and can only see what I've seen before. They're usually relaxed enough by the humor of that to make a suggestion, and there have been some pretty good ones!

Ernie,

Thanks for understanding and support!

When I was working on this project my idea was to make a remote that works better than existng off-the-shelf options, like my favorite but oh-not-so-perfect Harmony. I still think smartphones would make the best remote because for instance
- it can seamlessly download TV guide
- it can socialize your TV experience
- it has touchscreen larger than any other remote (available for reasonable price). Plus the touchscreen itself is much better than in other remotes I saw so far
- you can easily find it hiding under the pillow :)

I also wanted to make it completely web-based, so people can use the same interface on different hardware.

Unfortunately this project appeared to be more time consuming than I expected, primarily thanks to mobile safari limitations which I discovered while writing the web interface. Possibly ios5 will fix them and I'll be able to return to the project, but so far it is on hold.

Andrey Mikhalchuk
(aka the rtfms.com guy)

here is the source code: http://rtfms.com/episode-4-turn-your-iphoneandroid-mac-pc-player-etc-into-a-universal-remote.htm#source

Andrey Mikhalchuk
(aka the rtfms.com guy)

Thanks for posting that, this looks like fun to play with.

If the Harmony is in any way a reference or standard to compare to, you will always have a remote that people will want to throw against a wall. Better not to do this with your smart phone!


What the HELL does that mean? People will be so interested when the TV is too loud, you pick up your phone, you open the program, you locate the Volume - button, then you hit it. Hit it. Hit it. Hit it. Hit it. Hit it (okay -- down five dB now, only ten more to go!). And the experience will now be social because people will be yelling at you to turn the thing down NOW or get a real remote?


Try this with your remote: start a DVR in playback. Go to Fast Forward to locate a place in the show. Prepare to go into play. At this point, you can choose to watch the TV so that you know where you are in the show, or you can watch the phone so you are sure that your finger is still lingering directly over the PLAY button. Chances are high that you will pass the place you want to stop or you will push the wrong spot on the screen.

This is a flaw in all touchscreen operation, not just smartphone, but the example you showed, with five or six commands on the screen, just doesn't cut it. You'd need at least all of the transport commands, plus volume up, down, and mute. If you've got those on the screen, the buttons are too small to accurately hover over while waiting for the DVR to get to the place where you want to hit PLAY.

This is not theory. This is why I changed from promoting remotes that are mostly touchscreen to remotes that have hard buttons where you can FEEL which button you're hovering over. And the operation shown in the video, where volume goes up and down one hit at a time, is worthless unless you're all by yourself.

Actually, I hate to mention it, but I keep getting the feeling that this remote is for the loner, one with nobody else in the room. I have taught couples and families how to use remote controls, and this approach falls very short of "universal" enough.


This doesn't mean that the remote has to go onto the internet to find the command when you push the button, does it? I don't think so, but I'm just asking.


See my comment above about a "research project," including no guarantee that the thing will even work.


Hey, I'd like a real explanation of how the two IRs work to get you the high frequency signal you need. When you first mentioned two LEDs, you said nothing about how they are wired. It's now obvious that some kind of timing or interference is going on between the two channels that gives light modulated beyond the frequency response of either channel. How?

From what I quickly read it "sums" the left and right channel to give you a higher frequency. From what I remember of science class somehow it would have to "time shift" one channel to give it the ability to overlap the two "waves" so that it doubles the frequency to 38k. Can someone that knows tell me if my theory is right?

And Ernie lighten up on the man a little, he's tinkering. Don't we all like to tinker? :)

Oh I didn't mean that HArmony is the best of the best of the best. I think I saw better remotes (on pictures). Also I saw people smashing their smartphones just like remotes. Harmony is just a good reference. A reference that a good smartphone-based system can beat.


Well, if the TV is working that means it is already turned on, most probably with some help of the remote/phone. So there is no need to run the program - it is already running. As about the performance - my harmony is like that, really slow. It takes several really long seconds to change the volume. On the smartphone you can actually program something like Vol-10 button that would make it 10 bars quieter. Or (if the smartphone is the only remote to be used) you can even make Vol=10 button that would set the volume to 10. Most universal remotes can't do that, for instance.


Right. Luckily I can make buttons on the smartphone screen as large as I like. I can change the skins and span the remote across multiple screens.


Well, the newer version of the remote has nicer design (still not perfect) with large buttons really easy to find and press. 6-10 buttons will easily fit the iPhone screen, the rest (less frequently used buttons) can go to the other screens. Harmony does similar thing, just less customizable.


Yeap, it's hard to beat the hardware buttons, you're totally right. I just think that smartphone remotes have enough benefits for people to forgive this inconvenience. As about the remote performance in the video, that's just proof of concept. It was slow because safary was actually downloading the file from the server each time (sic!) and than launching external program to play it. I now have much faster prototype, though as I mentioned before it is still not fast enough because of some artificial limitations safary introduces.


I hope I'll have time to develop something more usable later :)


Yeap, it shouldn't. The one in the video actually does that, this is why it is slow (see above). I solved the problem in the newer alpha-quality code, but only partially.


Right.


It's in the video and in the blog. The brief explanation is
- each LED blinks with 38/2 = 19KHz frequency
- the phase is shifted 180 degrees
- the resulting frequency of the sum of both LEDs is the sum of frequencies of each LED = 38K

That's really brief explanation b/c there are at least three different ways to wire the LEDs and they use different principles to double the frequency, but as a brief explanation that works. You can find more details in the text blog, there are drawings on the stickies showing the picture of what's happening with the LEDs.

Thanks for good criticism - I'll definitely take it into consideration if I have a chance to continue this project.

Andrey

That's right. The phase shift should be exactly 180 degrees to sum the frequencies properly. Also LEDs threshold plays significant role here (check out how charlieplexing works), you need to generate the signal so it turns the LEDs in precise intervals. There are a lot of small things about it and I spent plenty of time perfecting the parameters of the code.


Thanks for support! :)

I didn't think you held it up as the best. You said something that implied you used it as a reference. It's a poor choice as a reference.



See, right here is a reason that you should not have been thinking of Harmony performance. This slow of a change is TOTALLY unacceptable, so if you're duplicating it, you're wasting time. Let's get together on a URC program or an RTI program so you can see just how slick today's ordinary integrated remote is. New car designers don't park 1936 Fords outside so they can glance up at them and think while they are designing new cars!


Problematic if you want it 5 bars or 15 bars quieter. More buttons would allow better trim but would clutter the screen.


Any programmable remote can do that IF THE UNIT HAS THAT COMMAND in its memory. That was capitalized because it's a big IF.


But moving across screens slows down action. I think this idea might work for an iPad sized device; note that Crestron has been doing this for years and the first Lexicon remote (made by RTI, incidentally) was about three pounds of 6" touchscreen.


Again, your reference point leaves you not being able to compare what already exists. Some URC and RTI remotes are totally customizable, with huge numbers of possible screens.


And that exists in the programmable remote world, too. I have a macro on a URC MX850 that advances 30 seconds eight times. The problem is that the 850 has a non-editable delay of 0.3 seconds between any two commands, and sometimes the DVR gets to where I want it to be before the 850 stops spitting out commands.

Just offhand, I don't get how 19 kHz, twice, exactly out of phase by 180 degrees, gives 38 kHz. I'd suspect it had to be 90 degrees out of phase. I'll mull this one over. I know already that it has to do with duty cycle and I haven't puzzled that out yet.

Thanks for coming on here Andrey. your article was a great read. a couple of questions if you don't mind:

1. storing audio will be a PITA as the buttons and numbers of devices adds up. Is there a way to generate a digital representation instead of analog to push out the LED for IR? If you can figure out this conversion mechanism it would help tremendously.

2. did you ever try the 940 LED? What is the range you are getting? Is there any LED which might be better than the 940?

3. how can i tell if a jack plug is molded or not without cutting it up. i want the screw kind of jack plug like you had. can i just get them at radio shack maybe? the molded kind have bad solder points also so i want to stay away from them.

Sure :)


I think so. I only used wavs for the sake of portability. Almost everything can play .wav files and you can even use them in a web interface. For generating the pulses a platform-specific program is required.


Sure, the LEDs I used in the video are 940nm. I've got a bunch of higher-performance LEDs, but never had a chance to try them. Also afaik 940nm seem to be optimal wavelength as it is the most typical wavelength in used in remotes according to Wikipedia. The LEDs from old remotes would probably work best because they have wider-angle lens. Narrow angle is the one of bigger problems with the hack-remote in the video.


I've got mine from ebay for $1 per count. If Radioshack they cost more, so probably salvaging a plug from some broken headphones or cables is the cheapest option. I actually managed to solder wire to molded type too, but it's not the most pleasant experience as burnt plastic smells terrible.

Good luck,
Andrey

I haven't seen any harmony of the last 6 yrs that has any delay between sending commands once things are turned on. Also imagine your phone rings while the TV is turned up. How do you turn it down? Please name one TV brand that has IR commands that allow you to send a single command to set the volume at a certain level, ie button press 8 sets volume to 75%, button press 5 sets volume to 45% About the only way to do set volumes is through RS232 or IP commands.



I'm glad to see that my brain still thinks right.

for portability sake i would think you would want to go the digital route as all of the existing IR codes online come in a digital format. i think i read somewhere that you could convert pronto code to the wav file. could i just use the pronto code directly and have the app convert it to wav file if needed on the fly? do you know the algorithm for these types of conversions?

also i thought i read the regular LED you used were 950 and the 940 were the higher performance LED. that is why i asked specifically about 940.

If you're wondering why someone would do this. Here is a reason. I am a quadriplegic i use voice control for everything. But you can't use voice control to control apps on the iphone. But you can use it to play music. get it! Cheap and easy vc universal remote. I can even add wav files together to make macros. surely you guys are smart enough to make a dongle. Supplies cost about 5 bucks from the shack. this is a very good solution to my problem. Inurance payed 5 grand for my last setup that stopped working.

i already made the dongle. just haven't gotten around to trying to make .wav files to test it. that's the PITA part. that's why i was saying if the .wav could be digital files as there are already digital files for all of your IR devices on the internet (especially on this one). It's insanely hard to build up a dbase for all of the IR products on the market via .wav files. Even for digital files if it wasn't for people like the CI on here posting files we would be stuck in the same rut. Instead I can build an app and incorporate tons of devices right off the bat for people to use right away. also for dongle solution you still have to point device in the direction of thing you want to control which may be an issue for some people. since there are boxes on the market that can do this kind of control and they already support digital files it would be nice to utilize the boxes and the standards they conform to which are already common in the industry for some time. this way any CI could do the setup for you instead of having to find someone who specializes in something.

for the voice control on iOS maybe Siri can help at some point. i have to look if there is a voice api for Siri like there is for Android. This is an area I have an interest in also for our apps. I totally agree with where are you going with your post about voice control. i just think there is a better solution to implement it. i know on Android there is. Just need to see if iOS is that open yet.