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Physical UI (OLED + Buttons)

The ground station has a 128x64 pixel OLED and four tactile buttons. Together they give you status at a glance and a menu system for configuration, pairing, and network control. No laptop or phone required.
Ground station OLED display showing WFB-ng link statistics

Hardware

OLED display. SSD1306 or SH1106 driver IC, 128x64 pixels, I2C interface at address 0x3C. Wired with four connections: SDA, SCL, VCC (3.3 V), and GND. The 1.3” size is easier to read in the field. The 0.96” size works on the bench. Buttons. Four 6mm tactile momentary pushbuttons. Each wires between a GPIO pin and GND. The agent enables internal pull-ups in software, so you do not need external resistors for the bench build.
ButtonPi 4B GPIOHeader pinShort pressLong press (2 sec)
B1GPIO 5Pin 29Menu upToggle recording
B2GPIO 6Pin 31Menu downToggle WiFi AP on/off
B3GPIO 13Pin 33Select / enterStart drone pairing
B4GPIO 19Pin 35Back / exitFactory reset (hold 10 sec)
Long-press events fire on release, not at the 2-second mark. If you hold B4 and change your mind, just let go before 2 seconds and nothing happens.

Status screens

Five auto-cycling screens rotate every 5 seconds. Press B1 or B2 to advance manually. Shows the WFB-ng radio link to the drone.
Link
RSSI  -52 dBm
Rate  8.5 Mbps
FEC   1204 rec / 2 lost
Chan  149 (5 GHz)

2. Drone

Shows the connected drone status.
Drone
ID    ados-drone-5e9a4c
Mode  LOITER
Batt  82%   12 sats
Alt   45 m  Spd 3.2 m/s

3. GCS (connected clients)

Shows who is connected to the ground station.
GCS
HDMI         PIC
192.168.4.23  observer
192.168.7.2   observer
The PIC badge marks the pilot-in-command client.

4. Network

Shows current network state and uplinks.
Net
AP   ADOS-GS-5E9A  192.168.4.1
USB  192.168.7.1    connected
Up   wlan0-client   OK
4G   disabled

5. System

Shows SBC health and agent version.
System
CPU  22%   RAM 640/4096 MB
Temp 51 C  Up  2d 14h
Agent v0.5.3
All text renders at 8x16 pixel font size so you can read it with reading glasses at arm’s length. Press B3 (Select) from any status screen to enter the menu. Navigation uses the same four buttons:
  • B1: move up
  • B2: move down
  • B3: enter / confirm
  • B4: back / exit
Main Menu
├── Pair with drone
├── Network
│   ├── WiFi AP on/off
│   ├── WiFi client scan and join
│   ├── 4G modem status
│   └── Uplink priority
├── Radio
│   ├── Channel (1-165)
│   └── Bitrate / FEC profile
├── Display
│   ├── HDMI resolution
│   └── OLED brightness
├── System
│   ├── Version
│   ├── Reboot
│   └── Factory reset
└── Back to status

Factory reset

Factory reset is a two-step process to prevent accidents:
1

Hold B4 for 10 seconds

The OLED shows a countdown: “Factory reset in 10… 9… 8…”
2

Confirm within 5 seconds

The OLED shows “Confirm? Hold B4 again for 3 seconds.” Release B4, then hold it again within 5 seconds.
3

Reset begins

The agent erases pairing keys, resets config to defaults, and reboots. The ground station returns to the first-boot state.
If you release B4 during either hold, or if the 5-second confirm window passes, nothing happens.

Power saving and burn-in protection

OLED screens can develop burn-in from static content over long periods. The agent includes three mitigations:
  • Auto-dim: brightness drops to 20% after 60 seconds of no button activity
  • Pixel invert: white-on-black swaps to black-on-white every 10 minutes
  • Screensaver: a small bouncing “ADOS” logo appears after 5 minutes of idle
Any button press wakes the display immediately.

Graceful degradation

The OLED and buttons are optional. The ground station works fine without them.
Missing hardwareBehavior
No OLEDAgent skips the OLED service. All menu functions are available via the setup webapp and Mission Control Hardware tab
No buttonsOLED still renders status screens on a 5-second cycle. Configuration is done via setup webapp or GCS
No OLED and no buttonsAgent runs headless. Use WiFi AP + browser, USB tether, or HDMI kiosk for all interaction
On boards other than the Pi 4B, GPIO pin numbers are defined in the HAL board profile YAML. The agent reads the board profile at boot and maps buttons accordingly. You do not need to edit any code.

Remapping buttons

You can remap what each button does (short press and long press) from three places:
  • OLED menu: not available (you would need buttons to remap buttons)
  • Setup webapp: Advanced page
  • Mission Control: Hardware tab > Physical UI sub-view
The button remap matrix supports any combination of actions: record toggle, WiFi toggle, pair, reboot, factory reset, cycle screen, and more.

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