10/5/2025 11 AM - Started making the Schematic

Hello, World!
I settled down to a ICE40UP5K-SG48I since it has a QFN package and an OK number of LUTs
Found a crystal suitable for the fpga, and started building the power rails.
I also tried making a power supply filter, but I can't seem to add ferrite beads to the schematic (I'm using Easyeda Pro).

Note that the voltage regulators are still to be chosen, since I want to power an rp2350 on the same board too.

10/5/2025 9 PM - Habemus schematic!

INSANE rp2350 && ice40 schematic speedrunning session
Just mostly need to get the 40-pin connector in-place
I still have to find the perfect ferrite bead


I also need to add an SPI and UART connection between the rp2350 and the ice40.

By the way, you might be wondering what are those strangely-routed USB and USBc female ports are for, and I will be using those to see if I can make my own TCP/IP stack on the fpga, as a nice side-quest.

10/21/2025 - Routed?

Today I changed switched of my capacitors to be 0402, I also placed the components on the pcb and routed them, for the most part.

I also decided I will use a 4 layer board with Signal-GND-3v3?-Signal layout.
I have a few doubts if I have positioned the inductors for the rp2350 regulator correctly
Did some of the work in class because I was bored =D

10/26/2025 - Routing session #2

Re-did the wiring of some of my components, added routing to the headers
I have yet to find the use for 10 pins
also to add is a nice reset button for the fpga and maybe a programming port

10/30/2025 - The end?

Hi fellow readers, today I added 4 small neopixels on the top-right of my board, fixed some of my extremely janky routing for the headers, added some debug headers for the rp2350 and a button to reset the ice40.

I am most likely finished with this board, just needs some polishing and some silkscreen art :)

11/3/2025 - smol update

Fellow readers, we have reached the end, wanted to show you a final pcb screenshot of the wiring, I routed cdone and reset pins out to the headers to be able to program it.
Here follow the rest of the pcb stackup

11/22/2025 - Final touches

Added mounting holes, I also added a user-button and a few LEDs, switched the old oscillator for a new one (a bit bigger, is a bit better, and also lowers my pcb price).

12/14/2025 - Blinkmaxxing

Hii, I received a package a few days ago and tried the onboard RP2350 with some NeoPixel code,
firePI neopixel demo
I then tried sending some bits back and forth with the FPGA after not being able to figure out how to make it work for a while.
I also made my own iCE40 flasher, utilizing an external Raspberry Pi Pico (thanks to ChatGPT for the SPI instructions for the flash chip).
I made my own Verilog shell and Makefiles, and made a small blinky program.
(This is my first time writing Verilog for an FPGA!)

12/23/2025 - Quantum maxxing

Hii. So I decided the most reasonable use of an iCE40UP5K was obviously to make a small "quantum emulator”, because it felt badass, and I literally wrote "quantum" on the silkscreen so that felt like the perfect opportunity.
I don't expect full tickets for this devlog, though I really want to show others what I made :)
I made a 2-qubit emulator, with just real amplitudes (for the sake of simplicity), and a bunch of gates.
I used Q2.14 numbers because floating points are inaccurate at low bit counts and high bit ones are really expensive.
You can control it over uart and send commands like: "r"(reset state), "h0/h1"(applies quantum hadamard gate), "c01/c10" (applies CNOT gate given source and target qubit, "m" (to collapse the "wave function" and collect a reading), and lastly "e", used to send the qubit state and """entangle""" it with another board's

Here I "entangled" 2 qubits to either output 00 or 11!

I made it so an orange light appears when the cpu is in a quantum state, and a green one when it's deterministic.

If you want to try it out, there's the full code on the github page, with the flasher, python UART shell for the rp2350 side, and the fpga code, with a makefile and nix-shell, in case you need it.

Oh btw here are the neopixels working!

Hit me up on slack if you're trying to reproduce my setup or want to make a board like mine and need some help!