Two years ago I used wled and WeMos for my Christmas light display. Lots of hand made wiring.

Decided i wanted to learn how to make a pcb and play more with Wled.

This is what I made…

5 outputs
Screen which tells me if it working via xlights or wled
Thermal sensor (which is always 3 degrees wrong)
Relay to power of the PSU for the lights


Nice project, I was trying to do a similar project on my own. Could you share the pcb file? I really want to learn how to do a project similiar like this.

which pin do you use for the data led output?

Hi, really locks like wonderfull project. I am trying exctly now to do something that really work very well.
I am experiencing some probles with ESP32 MCU when connecting with 74HCT125 a lot of noise…
In your project I see you use a Bus Transiver 74245. Why do you use this component?
Would be possible to share with me the Schematic and the firmware that you used or modified?
I really loved the idea of an OLED Display…

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The 74HCT245 is essentially an 8 port version of the 74HCT125 (only 4 ports) they are very much the same type of IC.

Couple of things to watch out for if you’re getting “noise” (flickering, jitters, etc) on your strips:

  1. Make sure all unused inputs on your 74HCT125 are set to +5v or 0V, don’t leave any inputs disconnected or “floating”. That’s a common way to cause all kinds of noise issues.

  2. Make sure you have a 100nF (0.1 uF) disc ceramic capacitor connected near the Vcc pin and going to ground. This is a standard power supply bypass capacitor and another way to decrease noise.

I was using the 74HCT125 and moved to this larger chip.

I have actually left unused Pins floating. So I’m going too have to see if I notice any flickers


Lots of this was trial and error. (A lot of error)

Basically the firmware is just the usermods… Found this hard to get my head around with.

The 4 line display usermod i did tweek. I use x-lights so the screen tells me if xlights is controlling it or wled. Again lots of trial and error.

If your looking for ideas, go to easy eda and search wled. Thats what I based by board on.


For long term reliability, you’ll want to tie those pins Hi (or Lo).
You can use something like a 10K pull-up resistor so those inputs could easily be used in the future.

Floating inputs is a sure way to get “unexplained results”…


So I’ve had think…

I’ve connected my relay to one of the pins - so if I don’t need a relay I can steal the pin for an output.

Another to the thermal sensor. Hoping this will solve why I’m always off by 3 degrees

Might as well put then to use!

That leaves me with one input/out spare. Done some reading on floating pins. So I think i can just set the last input t GND?

As long as you tie the input(s) to a fixed Hi or Lo, it won’t affect stability. Remember to associated tie the OE input as well. On the 74xxx125 devices, that’s another 4 lines to keep track of…

Have noticed my current floating one randomly pauses!