Raybox-zero chip: Open-source silicon ray caster 3D game; Tiny FPGA/Verilog "GPU" ASIC | sky130 VLSI

Short presentation: my simple ASIC concept design of a 3D-like "ray caster" video game hardware accelerator chip, FPGA-tested, then synthesised/submitted to TT04 (Tiny Tapeout 04) for VLSI/ASIC manufacture. Created with OpenLane and the sky130 process (Google/Skywater 130nm Open PDK).

Designing and getting a real silicon chip made is now available with such a low barrier to entry. After learning the ropes and dabbling with FPGAs, Verilog, and other HDL/RTL concepts, I created this retro-inspired hardware implementation of a simple 3D ray caster that follows the principles used by Wolfenstein 3D, and sent it off to be manufactured on a microchip along with 142 other community designs.

00:00 - Intro
00:55 - Background
01:56 - What is Raybox Zero?
03:05 - Ray caster features
05:21 - Demo video & interaction
06:09 - Working with VGA
07:49 - How it works: Maths
08:47 - How it works: Tracing FSM
10:34 - SPI interfaces
11:36 - Development
12:56 - Code & documentation
13:46 - Questions & answers
16:09 - Concluding thoughts

=== Amazon affiliate links for products mentioned ===
/// VGA to HDMI converters:
-- VENTION VGA to HDMI Adapter: https://amzn.to/3vjv9Hk
-- Duttek VGA to HDMI Connector Cable: https://amzn.to/4ahE1fx
-- Mini 1080P VGA to HDMI Adapter (white): https://amzn.to/49V424u

/// Other FPGA/VGA and related hardware:
-- PMOD-VGA (VGA DAC/buffer): https://amzn.to/3TKyUPm
-- iCESugar FPGA Dev Board inc. PMOD-VGA: https://amzn.to/3ThOBfG
-- Digilent Basys 3 Artix-7 FPGA board: https://amzn.to/3TodyGj
-- Raspberry Pi Pico: https://amzn.to/3PtdCDy
-- Pi Pico with soldered header pins: https://amzn.to/3PtJCHy
-- Soldered Pi Pico W (w/ WiFi support): https://amzn.to/3PtoQYx

=== Links to resources mentioned ===
-- First raybox-zero journal entry: https://github.com/algofoogle/journal...
-- Main raybox-zero git repo: https://github.com/algofoogle/raybox-...
-- TT04 wrapper git repo: https://github.com/algofoogle/tt04-ra...
-- Zero to ASIC course: https://zerotoasiccourse.com
-- Tiny tapeout: https://tinytapeout.com
-- Efabless: https://efabless.com
-- Aliaksei Chapyzhenka's (drom's) reciprocal approximation: https://observablehq.com/@drom/recipr...
-- Verilator: https://www.veripool.org/verilator/
-- cocotb: https://www.cocotb.org/

Special thanks to Matt Venn for use of spinning wafer footage:    • Rotating die & wafer videos with CC BY lic...  
...and clips of Zero to ASIC Course videos:    / @zerotoasiccourse