Addressable LEDs

Programming Support
1

Hey yall, first time posting!

I’ve been trying implement an addressable LED strip on our bot, and I’ve been reading up on some documentation, I’ve tried to use the method listed on the VEX Pros API documentation but I cant seem to get it work, I read on past posts that the number of LEDs on the strip could be a problem (60), is that still the case? I also have not seen any posts on this topic past 2022, so I wonder if there is something that’s happened since that I am not aware of.

Thanks in advance!

2

see this post

3

i need to talk to my programmers but could you use these with vexcode? We used leds in FRC and loved them but I dont know that with us its possible in vrc. WOuld we have to transfer to vs code or pros to do this?

4

You could with C++, the code linked here could be easily ported.

or for Python.

5

I understand that and did in fact look into that, but thus far all my bot’s code have been written in PROs, and it would be a difficult pivot, is there no way to resolve this issue in PROs?

6

I’ll go try the solutions listen here, thank you!

7

It should work ok from PROS, I did a quick test using latest kernel.

void initialize() {
    pros::lcd::initialize();
    pros::lcd::set_text(1, "Hello PROS User!");

    static pros::adi::Led led (1, 60);

    pros::delay(1000);
    led.set_all(0x800000);
    //led.update();       
    pros::delay(1000);
    led.set_all(0x008000);
    //led.update();   
    pros::delay(1000);
    led.clear_all();
}

led strip in port A of internal 3wire, seems to work ok, my strip has level converter inline. See if something simple like that works.

8

Sorry, I’m not the brightest of the bunch :pensive:
Could you please explain what a level converter is?

9

It may or may not be the problem, some strips will work ok, some don’t without the level shift.

10

would these be counted as microcontrollers and technically not allowed under vex rules?

11

What are you using for the 5V source? It doesn’t seem possible to reach 5V exactly with AA batteries.

12

Hey guys, so sorry
it was something so stupid. the pins at the end of the led strip were female, I plugged them straight into the brain thinking the triports on the brain were male

It wasnt plugged in at all

im so sorry yall

13

If it works now then no worries, it’s all good.

14

For me the 3.3v from the triport just works, but I think thats only for some LEDs.

15

Sorry to restart and old post but to actually wire the LEDs you are just soldering the 3 wires from the LEDs to the 3 wires on the VEX DuPont style connector right, or do i need to find a certain strip with them already on there, also if you do have to solder them to the 3 wire DuPont do I need to do it in a certain way/certain wire to wire. I haven’t soldered them on or even bought any strips yet, I know what I want out of my LEDs (I’m a tiny bit of an LED Nerd for my FRC Team) but I am not sure how to legally and correctly connect them to the brain. I think they’ d look amazing (I was a big fan of the Radioactive bots with the LEDs)

16

You just solder them, but you have to flip some of the wires. What we did last year was take the female connector off of a 3-wire extender cable, strip some of the wires, and solder it, then put heat shrink around it. This worked, but was a bit unreliable (sometimes you had to press the cable a certain way or wiggle the wires to make it light up all the LEDs correctly) but that was probably because of bad soldering. Here are some photos:

With wrap on:

IMG_3990
IMG_39901920×1440 198 KB

With Wrap off:

IMG_3994
IMG_39941920×2560 249 KB

Note that you have to twist the cables when you solder them, as the order is different on the pads then in the VEX 3-wire cables.

17

alright, thank you for the help, ill get them ordered asap