me and ili have been working on a custom gba cart with IO expansion and such. I've been working on the audio side, and maybe have been getting a bit carried away.

Got this, takes line in on the right, line/headphone out on the left, with processing in the pico

I've added sliders tonight, so time to make them do something sadly i dont think they'll fit into the gba cartridge...

it's not exactly related but I need to write this down *somewhere*. i was having an issue with pipewire where whenever i'd launch steam games on my thinkpad p14s gen 5 (intel), audio playback would be totally blocked until i closed them.

tangent

a workaround I used previously was to just use pulseaudio. unfortunately this fell apart as soon as I wanted to play a game *and* capture its video and audio in obs, i'm on wayland and afaik *need* pipewire for that to be possible. whee!

i found that removing the connections between the game and the output device in qpwgraph and putting them back would restore audio (for the game and everything else!), but if basically anything happened that added or removed a connection to the output device (say, a notification sound being played, or opening the volume control plasma widget) it would break again until I re-added the connections.

i eventually stumbled on this: https://gitlab.freedesktop.org/pipewire/pipewire/-/issues/618

Quote from: Wim Taymans on gitlab.freedesktop.orgTry setting api.alsa.headroom = 1024 in /etc/pipewire/media-session.d/alsa-monitor.conf

that ended up fixing it, but I had to figure out how to adapt it to wireplumber. here's what I ended up with:

# ALSA node property overrides
# docs: https://pipewire.pages.freedesktop.org/wireplumber/daemon/configuration/alsa.html
# to reload,
# systemctl --user --now restart wireplumber

monitor.alsa.rules = [
  {
    matches = [
      {
        node.name = "~alsa_output.pci.*HiFi__HDMI1__sink"
      }
    ]
    actions = {
      update-props = {
        node.description = "HDMI1 Out" # less verbose
        api.alsa.period-size   = 1024
        api.alsa.headroom      = 256 # introduces latency for badly behaved drivers; 256 seems to work, 2048 may be a decent option idk
      }
    }
  }
]

what that setting actually does (reference):

Quote from: pipewire docsapi.alsa.headroom

    This adds extra delay between the hardware pointers and software pointers. In most cases this can be set to 0. For very bad devices or emulated devices (like in a VM) it might be necessary to increase the headroom value.

    Type:
        integer (samples)

i need to start collecting notes like this somewhere. like a "web site"

...the fact that it doesn't output anything to indicate that that's what's happening is a little absurd

hey so I learned today I was wrong about the akmod thing!

when booting after a new kernel is installed, my laptop would sit at a black screen with a flashing prompt, and the fans would spin up. i assumed this meant it was unrecoverably dead (because in my experience, that's usually what that means!) but during that time it's actually *synchronously building the missing kernel module*. so all i had to do was wait!

this page which is like, the canonical source for "how to use nvidia gpus on fedora" doesn't mention that at all 🙃

Quote from: lifning on May 03, 2025, 03:43 AMAT&T Archives: The UNIX Operating System, a presentation largely by a young Brian Kernighan

Can highly vouch for this one. This was what made the whole UNIX system idea "click" for me when I was in high school. It's so in-depth and yet approachable for those who might not understand the technical aspects.

---

Somewhat relatedly, while I'm not sure most would consider them talks:

"How I Became a Phone Phreak" series by Evan Doorbell (YouTube playlist)

If you aren't familiar with Evan Doorbell's tape collection, this is probably the best place to start. The story of a "classic" phone phreak getting his start in the circle by way of curiosity in the weirdness of the old Bell System. The "Production Tapes" collection is actually a narrated tour of actual tapes Evan kept from the '70s to today, with this series being the most edited of the bunch.

AT&T Archives: The UNIX Operating System, a presentation largely by a young Brian Kernighan

Describes how the UNIX pipeline and philosophy empowers users to solve their own problems by composing existing, simple programs together without having to write new programs outright. This is something those of us who've used UNIX shells for years take for granted by now, but there's something really enjoyable about seeing Bell Labs folks articulate their then-new idea for this paradigm, and seeing how much of it is still very relevant today.

it is Bandcamp™ Friday®, which means i have purchased the 2025 remaster of Gay Bar by Electric Six and spliced the first verse with that of its Japanese radio edit

...okay i had no idea the WYSIWYG mode even existed. very impressive that you got this working with that!!