I'm looking at controlling some WS2812 LED strips with an Arduino (possibly a Pro Micro Leonardo) so that I can control the LEDs when I play a note on my piano and have LEDs light up above the keys.
I'm sure I will probably have lots of questions on the code side of that as time goes by however there is one thing which is totally baffling me at the moment regarding the spacing of the LEDs on these strips which is what I'd like to ask a question about if that's okay?
I've seen on various YouTube videos people with LEDs above the keys on their keyboards / pianos and they all seem to have 2 LEDs per key however looking at the datasheets for the LED strips (in the videos they all say they're using the 144 LEDs per meter variety) the distance between the LEDs doesn't seem to add up to me.
I found a datasheet which had the LEDs as being 5mm wide and 8mm between the centres of each LED. By my reckoning (unless my calculations are completely off - has definitely happened before!!) that means 13mm from the left side of the first LED to the right side of the second.
As the white keys on most pianos are between 24-26mm in width I can't see how for some magical reason the strips line up with the keys?
Is there something I'm missing somewhere or do the datasheets perhaps have the wrong sizings on them?
Many thanks for any help with this as I've been looking at all the various sizes and loads of videos of people with them on their keyboards / pianos and they all seem to line up except the sizes on the datasheets say to me that they shouldn't be able to!
Thanks for anything anyone might be able to let me know about how they've done this as I'm totally confused at the moment as to how they've managed it.
I have a professional stage piano (Yamaha CP1) however there's no way that the key sizes on the pianos I'm seeing on YouTube could be as small as these LED strips are making out as nobody would be able to play them!
Best wishes,
Mark
P.S. Not sure if there's a better place to ask this but I don't seem to be able to login to the forum on my desktop machine (currently posting this from my phone) as when I click on the 'SIGN IN' button at the top right of the page it just refreshes the current forum page that I'm on and never takes me to the sign in page. Pressing the same button on the main Arduino.cc page allows me to login but then as soon as I come to the forum I'm logged out again and can't login! If anyone knows why then I'd really appreciate being told how to login to the forums on a desktop machine. Thanks everyone.
Hi Mark; when you connect to arduino homepage you should have a screen as signin.png
Just click on SignIn and follow.
Some LED strips are " cuttable ", so you can separate them individually.
Look carefully at the pic, you see copper tracing between LEDs where you can cut and separate.
Youll need to solder wire strips to fit yourneed.
Just be careful NOT to flip any LED; they MUST be soldered with the arrows in the same direction.
Im having problems uploading, hope you receive reply with attahments
Thank you very much for the reply and the attached images. I see what you mean now. Actually I printed out a sheet with the sizes of the LEDs with associated spacings on it and placed it on my Piano and I can see now where I was going wrong!
I was measuring the front part of the keys and couldn't get the LEDs to line up at all well but placing the strip I printed at the back of the keys (where they would actually go anyway! Duh silly me!) and it seems to line up pretty nicely. May have to cut at every 24 LEDs (1 octave) and space out very slightly but don't think that will be too much of a problem.
With regards to the Sign In I'm really not too sure what was going on as I was doing exactly that but it was never signing me in. The weird part is that (I'll admit up front at one point I was getting a little angry with it all - had been a long day ) I tried clicking edit on the post that I'd submitted on my phone and that for some reason took me to the edit page with me all logged in. Really not sure what was going on there but every single time I was clicking on the Sign In button in the forums it was just redirecting me back to the same forum index. All very weird. Like I say though it did log me into the main Arduino.cc page so not really too sure what was going on there. All seems to be logged in and staying logged in now though so I'm a happy bunny.
Thanks again for your reply, it's very much appreciated. I'll probably be back in other posts asking questions about how to get this all working soon so that's a heads up warning for everyone to run a mile!
Don’t buy WS2812 LEDs as you will end up missing serial data as the data is sent out to the lights. Use the dot star type where the data transfer can be interrupted.
With regards to the Sign In I'm really not too sure what was going on as I was doing exactly that but it was never signing me in. The weird part is that (I'll admit up front at one point I was getting a little angry with it all - had been a long day ) I tried clicking edit on the post that I'd submitted on my phone and that for some reason took me to the edit page with me all logged in. Really not sure what was going on there but every single time I was clicking on the Sign In button in the forums it was just redirecting me back to the same forum index. All very weird. Like I say though it did log me into the main Arduino.cc page so not really too sure what was going on there. All seems to be logged in and staying logged in now though so I'm a happy bunny.
If after a sign in it still indicates that you need to sign in, close the browser tab and try again to go to forum.arduino.cc. If it still insists that you're not signed in, refresh the page.
As said,
Paul__B:
The forum software behaves in many mysterious ways!
Grumpy_Mike:
Don’t buy WS2812 LEDs as you will end up missing serial data as the data is sent out to the lights. Use the dot star type where the data transfer can be interrupted.
Hiya,
I'd been told by somebody that if I'm using the WS2812B LED Strips along with an Arduino Pro Micro then I wouldn't have any problems?
They have made one of these MIDI reactive LED strips and have a video of them playing it and I can't see any lost or stuck notes on their video so not sure if the board has something to do with it maybe?
They assured me that with the board I have and that LED strip that it would be fine so I'm hoping that's the case as I just ordered the LED strip last night and can't cancel it now.
Thanks,
WS2812B strips need to update the complete strip in one go and the process can't be interrupted. This takes time during which the microcontroller can't do anything else. That is usually not a problem till you also want to receive serial data. Because interrupts are disabled during the updateof the WS2812B strips, receiving more that 1 character becomes unreliable; there are easy workarounds once you understand the problem.
^^ I have them, be careful when buying from cheap source on eBay or Aliexpress. The first batch I got, the pads lifted very easily even when I set my iron all the way down to 250C (a bit more than enough to melt 37/63). Cheap glue binding copper layer to fiberglass base.
If anyone knows why then I'd really appreciate being told how to login to the forums on a desktop machine. Thanks everyone.
) I tried clicking edit on the post that I'd submitted on my phone and that for some reason took me to the edit page with me all logged in. Really not sure what was going on there but every single time I was clicking on the Sign In button in the forums it was just redirecting me back to the same forum index. All very weird. Like I say though it did log me into the main Arduino.cc page so not really too sure what was going on there. All seems to be logged in and staying logged in now though so I'm a happy bunny.
