Ask Lemmy

ESP32-S3 will do everything you want and then some. And you can do it all without any programming by using ESPHome. And they are incredibly cheap (starting around $3 a board and up depending on options).

There are more suited, fancier, better options, like using STM32FX microcontrollers, but that will require more knowledge, programming skills, and you'll find it harder to get help.

The atmega328 and stm32f411 are good. Both are well documented, have boards available with good peripherals, and plenty of other hobbyist projects on them.

The atmega328 is 8-bit. It was made by Atmel, which was a great company until they got bought by Microchip a decade ago. Their IDE sucks now, but you can still program them with other tools and IDEs.

The stm32f411 is 32-bit, a bit more recent, and a bit more expensive. ST microelectronics has great documentation and hobbyist support.

These are microcontrollers, so you'll be running without an operating system. If you want embedded Linux, you'll need something with an MMU and more power than a microcontroller.

I do model building with LEGO, and I use the Raspberry Pi Pico (which is different from a Raspberry Pi). For programming, I use the Arduino environment.

The controller has two cores, and, in the version I use it, has a wifi interface.

My models are modular and have a 12V power bus, and I use DC/DC adapters to generate the 5V or 3.3V needed for some applications. I use 12V because some lights and many motors needs them.

The controller has over 20 IO pins, lots of options for i2c and SPI busses, and the PIO system allows for easily driving NeoPixel displays.

The wifi is used to connect the processors to a central Mosquitto broker, so they can communicate, e.g. coordinating light effects or reacting to a button press somewhere.

I don't know shit about shit, but I really want to see your WIP and finished pics! This sounds like an awesome project.

I don't have the answer to your question but I applaud your ambition and willingness to reach out to the community before hand for help.

The main thing is that (as a relative novice) you're going to want something with a good community around it. Therefore, you want either Arduino, ESP32, or Raspberry Pi Pico.

There's a bunch of different ones with different features that may have varying usefulness for your particular situation, so nobody can tell you exactly which ones to get down to the model number. You're just going to have to read the data sheets to figure out which to buy.

Regardless, any reasonable choice ought to be obtainable as off-brand clones in a multi-pack from Aliexpress for single-digit dollars per unit.

Personally I'm a big fan of Adafruits ItsyBitsy 32u4. Loads of potential in a small and cheap backage. Enumerates as an arduino via the USB port, so no special hardware is requires to program it. I use one to read a PWM signal and measure the pulse width on a few channel, so I would think it's capable of outputting similar signals, which comes in handy for contrilling LEDs and small steppers.

If you want to control something a bit more power hungry via PWM you might want to look into PCA9685 which works really well with, for example, a raspberry pi zero.

What kind of scavenged screen? Laptops? Because non-laptop small lcds are an undocumented mess. You'd do better to buy screens that work with esp32s.

I think if you don't already have a more solid plan than that, then this project is probably too complicated for now, and you might start with a single display. If the origina megacity is 22 miles across (fairly small for a megacity) then 1/220th of that is 1/10th of a mile which is pretty huge. A standard 48 foot billboard would scale to 2.6 inches wide.