Hi we got the 12v leds from rev recently and they come with 4 cables: one for 12v and 3 for the rgb. We want to connect it to our roborio for control and to our vrm for power how can we do it?
The 12V strips that REV sells are not individually addressable.
12V RGB: 12V RGB LED Strip - 5m - REV Robotics
5V addressable: 5V Addressable LED Strip - 1m - REV Robotics
The 12V ones are wired in parallel for R, G, and B, so the entire strip will be one color. You need to have a high current driver like the REV Blinkin to supply enough current for each color.
If you actually want individually addressable LEDs (so you can create patterns by controlling them from the Rio individually, with a single 5V supply), you will need a different strip—while REV is out of stock on those, they are readily available from other sources, search for WS2812 or WS2812B.
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To expand on this answer, the LED strip you describe is not really what is commonly called an “addressable” strip.
You have one PWM control line that controls the intensity of all of the red, green, or blue LED elements. You can control the color of the entire strip, but every LED in the strip will be the same color.
As the above circuit diagram shows, these can be tricky to interface with a microcontroller because of the voltage and power mismatch. Your micro needs to be able to sink enough current into a digital pin to light all of the LEDs in the strip, or else you need a transistor or other driver to amplify the digital signal. You also have issues with voltage, because your LEDs want to run at 12V, but your digital GPIO pins want to be at 5V. (The circuit, above, takes care of the voltage mismatch through the driver transistors.)
It is much simpler to use actual addressable LEDs, and then you can run multicolor patterns. These have only 3 connections: ground, power (usually 5V) and data. The data line is a serial connection that can be wired directly to a Roborio GPIO pin, and the power lines connected through an appropriate voltage regulator to your power source. (Note, you also need the voltage regulator for the type of LED strips you already have.)
There is excellent support in WPILib for addressable strips. It should only take your programmers about 20 minutes to have it up and running.
The electrical interfacing is easier, and you get independent control over every LED in the string. I know you already purchased the other type of LED strip, but these strips are relatively inexpensive, and the benefits are great.
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Just to add to this.
with the self control unit, you will be down to just 1 string of LEDs that you can control (at least last year’s WPILIB not sure about this year if they were able to increase that or not).
For higher current driving, you can look at the REV’s Servo Power module - Servo Power Module - REV Robotics as another alternative.
I amAndyMark not sure why this is always presented as a major limitation. You can control one string of up to 5,000 individual LEDs, which can be cut into shorter segments wired in series. We have also run parallel strings when all of them are running the same light pattern.
For reference, 5,000 LEDs at full intensity would try to draw approximately 300 amps from your battery.
Only tying up a single GPIO port on the Roborio to control that many LEDs is certainly NOT a disadvantage. The RGB LED strip the OP had purchased needs 3 GPIO lines per strip, and still can’t address individual LEDs in a string.
To add to the recommends for LED strips, we’ve had a good experience with these 5v addressable strips from Amazon. It’s four .5m strips, so it can actually be handier than the 1m strips Rev sells, since you can distribute them around the robot and still wire them together easily without having to cut the strips.
For control, why not just buy a Rev Blinkin LED Driver? They really are easy to use and it solves the whole problem of controlling and powering the LEDs nicely. Rev has them in stock again, so no problem getting hold of one and they’re pretty reasonable on the price.
Didn’t say it’s a BAD thing, just wanted to make sure people are aware (especially ppl new and/or ppl who don’t trend to read the Documentations…god knows I have dealt that from my own students more then I wanted to admit)…
When you frame it as “down to just one string you can control” then you are implying that it’s a bad thing.
/derail
Unfortunately, the NI team ran out of time to implement it for this year, but I’m hopeful it will make it for 2025.
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