Chapter 04
Display and idle clock
The panel always shows one primary scene. When nothing else owns the display, B0rd OS presents an idle clock — a clear face for wall time, with soft motion behind the hands so the sign still feels alive without shouting for attention.
Base preference
Every sign has a base preference: idle clock orlaunch countdown. The base timeline keeps running within that preference while a temporary notification is visible, then its current presentation is revealed. Fresh devices may arrive in countdown until you choose otherwise; either choice is valid for day-to-day use.
Change the base preference from the on-device interface or from the USB control plane. The change takes effect immediately; you do not need to reboot.
Idle clock behavior
The idle clock expects a trustworthy wall time. When network time has been established (or time has been set from the control plane), hands and readouts follow your timezone offset (net.time.tz_offset_min, minutes east of UTC) and optional label. Until time is known, the face may still appear, but countdown-style “time remaining” strings elsewhere on the product will not be meaningful yet.
The underlay motion is decorative. It is meant to keep the panel from looking frozen — not to compete with the time. If a notification is active, the system temporarily replaces that underlay with a higher-contrast pattern so the alert band stays readable.
Brightness and layers
Master brightness (display.brightness, 0–255) is the overall ceiling. Each display layer is a percent of that ceiling: underlay (FX) → base (clock / countdown) → notify. Defaults: underlay 12, base 100, notify 100.
| Key | Role | Default |
|---|---|---|
display.brightness | Overall intensity ceiling | 255 |
display.layer.underlay | Background motion (0–100%) | 12 |
display.layer.base | Clock / countdown chrome (0–100%) | 100 |
display.layer.notify | Notification overlay (0–100%) | 100 |
Full ranges: Settings reference. Raise overall brightness for sunlit rooms; lower it for nightstands and close desk use.
Mount orientation
If the sign is rotated on the wall, set display.orientation so text and chrome read correctly from your viewing angle. The firmware rotates the viewport after brightness and layer compositing, then sends the result to the HUB75 panel. Change takes effect on the next frame — no reboot.
Product default is 180 (inverted) for the standard M1A desk / wall mount. Use 0 when the panel is upright relative to the enclosure, or 90_cw / 90_ccw when the frame is sideways.
| Value | Meaning |
|---|---|
0 | Upright — no rotation |
90_cw | 90° clockwise (panel rotated to the right) |
90_ccw | 90° counter-clockwise (panel rotated to the left) |
180 | Upside-down (same as legacy display.rotate_180=true) |
Operator knobs (SoftAP)
On the SoftAP Display screen, open the main display controls (not Playlist). The Display orientation menu lists:
- 0° upright →
display.orientation=0 - 90° CW →
90_cw - 90° CCW →
90_ccw - 180° inverted →
180
Confirm save on the portal so the choice persists across reboot. USB uses the same key: settings set display.orientation 90_cw thensettings save. Full key tables:Settings reference.
Accessibility presets
A global accessibility preset (a11y.preset) can favor structure and luminance over subtle color: standard,high contrast, or colorblind safe. High-contrast modes strengthen separators and underlay motion so the panel remains readable when hue alone is unreliable. An optional reduce-motion flag freezes decorative animation. See also Features.
What can interrupt the clock
- Launch countdown — when selected as the base mode, the board replaces the clock with mission cards (and may share time back with the clock via playlist timing).
- Notifications — short overlays that restore the previous scene when they clear or expire.
Related: Night dim ·Eco sleep ·Launch countdown ·Playlist and scene timing ·Scene transitions ·Notifications ·Settings reference