Profiles and buttons

Every BadgeOS generation has three boot profiles, and U-Boot picks one based on the buttons you hold at power-up.

Hold the button while you switch the badge on, and keep holding it until the status LED stops blinking, since U-Boot reads the buttons at the end of its short countdown. (The verified-boot U-Boot has no countdown and reads them right away.) The buttons only pick a profile at power-up. Once Linux is running, BUTTON drives the LEDs and screens, and holding BOOT for 3 seconds switches cores.

All three profiles are part of the same generation and share USERDATA, so your files, keys and WiFi networks are there in all of them.

default

This is the everyday profile. The LED ring animates from early boot, and the optional OLED shows status screens and effects (see LED ring and OLED screens). The USB-C port is a USB device that gives your computer a network link to the badge, and with the Ethernet port it makes up the badge’s own routed network. BUTTON changes the LED pattern with a short press, the OLED screen with a long press, and the evaluator if you hold it for 5 seconds.

desktop

This runs Sway on the HDMI output at 1280x720, logged in as badge. The SG2000 has no 3D GPU, so the compositor draws with pixman and OpenGL programs run on llvmpipe on the CPU. The USB-C port becomes a USB host for a keyboard, mouse or hub, and the OLED engine is turned off.

The desktop comes with:

• badge-demo, “Nix Fixes This”, a 640x360 CPU-rendered demoscene production with a chiptune (Esc quits)
• badge-quake3, ioquake3 with the Quake III demo data, tuned for llvmpipe at 640x360
• badge-doom, crispy-doom with the Freedoom WADs
• the foot terminal

With a keyboard attached:

The games switch the output to a 640x360 mode, which has a quarter of the pixels to draw, and put it back when they exit. Sound goes to the monitor over HDMI.

The desktop is configured by the badge.graphics options, and badge.desktop.enable controls whether the profile gets built at all.

video

This is a clip player for HDMI that uses the SG2000’s hardware H.264 decoder and its video output path directly, without a compositor. It plays every *.264 or *.h264 file in /var/lib/nix-badge-video in name order. A short press of BUTTON skips to the next clip, and a press of 600 ms or longer goes back to the previous one.

The clips have to be raw H.264 Annex-B streams without audio. You can convert a video on your computer with ffmpeg and copy it over from any profile, then boot into the video profile:

$ ffmpeg -i in.mp4 -an -c:v libx264 -bsf:v h264_mp4toannexb -f h264 clip.264
$ scp clip.264 badge@10.55.0.1:
$ ssh badge@10.55.0.1 'sudo mkdir -p /var/lib/nix-badge-video && sudo mv clip.264 /var/lib/nix-badge-video/'

The player owns BUTTON in this profile, so the OLED engine is off. The badge.video options set the folder, the frame rate and the long-press time.

Factory reset

Holding BOOT and BUTTON together at power-up boots the default profile with a request to reset, and USERDATA is reformatted before anything mounts it. That removes everything you’ve changed, including your home directory and SSH keys, saved WiFi networks, edits under /etc (/etc/nix-badge included), and anything a deploy added to the Nix store. The system on the read-only store partition isn’t touched.

This is useful when a change to /etc stops the badge from booting properly, or before you give the badge to someone else.

With a data card in the slot, the reset formats the card’s EXT_USERDATA instead, and the eMMC keeps everything. Take the card out first if you want to reset the eMMC.

Changing the button mapping

U-Boot reads the profile names from its environment, in nixbadge_profile_default, nixbadge_profile_boot and nixbadge_profile_user (U-Boot and the rest of the software call BUTTON the USER button). An unset or invalid name falls back to the built-in one, and a profile that the generation doesn’t have falls back to default. You can change them from Linux with fw_setenv, though which environment that edits depends on where the badge booted from (see How BadgeOS boots).