I have a project that has 8 x RGB LED pushbuttons on a wired remote that is separated from the arduino by a few feet.
The buttons/LEDs all need to be controlled individually and instead of running 24 separate control wires for the LEDs, is there a way to build (or a board available) that I could send 3 wires (+,-,data) to, and treat it as an addressable strip? From there the board splits off to each individual LED?
Have you considered a WS2811 chip?
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You can try to use a shift registers (74HC595) or a I2C/SPI port expanders (e.g. PCF8574). I say "try" because it might not work over longer distances.
Depending on the drive capabilities and current requirements of the chosen chip, you might need drivers (e.g. transistors or ULN2003).
The above does not really make them addressable as in Neopixels but you can individually control them (not brightness).
You can also look at something based on the PCA9685 if you want to be able to control the brightness.
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Instead of making the LEDs addressable may be a better just to replace it with addressable ones?
You may multiplex (24 = 4Ă—6 =>10 wires) or charlieplex them.
Really depends on far "a few" is. Also depends on how many colours you want out of the LED. Also might depend on what voltage/current you apply to the LEDs.
Generally TTL signals, SPI, I2C are intended for on board use, while you can take them off board, flying leads tend to act as antenna, and you get more glitchiness as you increase distance and speed.
In the past I have simply used an RS232 connection to a satellite board like a Nano, which I can drive a group of LEDs, and depending on the number of LEDS also do PWM control.
Probably the way to go if there is enough space to add an IC + resistor and capacitors
That is another option.
Can you show us some pictures of that, which also illustrate how the leds are mounted and how much space you have right near them.
With WS2811's you could also mount those (and their external parts) close together and run much shorter wires to the LEDs
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I was assuming they are parts like this, but maybe the OP could inform us.
Those RGB push-buttons are exactly where I had to go the WS2811 route—especially if you have more than a few buttons to manage
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Doesn’t look like these are still available, but looks like someone had these buttons custom-adapted:
https://www.tindie.com/products/vre/illuminated-addressable-led-button/
You can buy WS2811 ICs and associate them with whatever LEDs you have (basically). WS2811 NeoPixel LED Driver Chip - 10 Pack : ID 1378 : Adafruit Industries, Unique & fun DIY electronics and kits
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Unfortunately the LEDs are already built into the buttons I have, so they are not able to be changed. I was hoping to not have to buy new buttons. Seems like there are a few good suggestions that I might try out first, and hope for the best!
If there is enough space i would go for WS2811's Do observe the connection diagram
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Actually no... I didn't know you could get the chip separately! That seems like the easiest solution thus far! Thanks!!
So some external components are required for it. And they are SMD
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Thank you for that! I might give the WS2811 chips a try first, as that sounds like what I am aiming for. I appreciate your option also.
Oh WOW! What are the chances?!... Those are the exact buttons I used! (Well, same design anyway...Minus the addressable LED). Very cool! Gets a little pricey once you need a few of them tho.
Yup yup! This seems like the winning solution so far! Thanks.
Keep in mind that the WS2811 provides 3 open-collector Outputs, how are the RGB tabs on the button connected now ?