Protogen Head part 13: Debugging DMA for SPI for the OLED Display
Channel: Elbrar
Date: 2023-03-25

I want to build a Protogen head using a frame I'm sourcing elsewhere and electronics and exterior finishing by myself. This is part 13 of the series, where I debug why DMA isn't working for SPI for the internal OLED display.

I post smaller updates on Mastodon while I'm working on the project (as well as general ramblings): https://furry.engineer/@Elbrar

I'm writing the bulk of the code for this project myself, using TinyGo.
Main code: https://github.com/ajanata/gotogen
Simulator: https://github.com/ajanata/gotogen-simulator
Text buffer: https://github.com/ajanata/textbuf
LED panel driver: https://github.com/ajanata/aykevl-things/tree/matrixportal-hacks
I2C DMA driver + other fixes https://github.com/ajanata/tinygo-drivers/tree/mine

00:00 Intro
00:19 Hooking Up the Logic Analyzer
05:40 Why Are the Control Pins Always Low?
07:35 Updating the Real Program
11:51 Why Does it Hang?
14:30 Performance Tests
19:14 Outro