BarnacleBoy ef9a7f40a8 add port layout and video output decisions

- Mechanical HDMI A/B switch for internal/external display toggle
- DisplayLink rejected: no ARM drivers exist
- 10-port layout split across 4 surfaces
- Port side: 4x USB-A, 1x USB-C data, 1x USB-C PD out
- Starboard: Ethernet, HDMI out, 3.5mm audio
- Bow: USB-C power input + fan exhaust
- Stern: handle, SD reader, Kensington lock
- Updated BOM with HDMI switch, panel-mount cables, SD reader
- Cost estimate now ~58

2026-05-12 07:18:54 +00:00

2.1 KiB

Raw Blame History

Port Layout

Overview

10 accessible ports + SD reader + Kensington lock, split across four case surfaces.

Port Side (Left, Facing Bow)

Data connections. "Plug and unplug frequently" zone.

Port	Count	Source	Notes
USB-A 3.0	4	Powered hub	Flash drives, peripherals, keyboard, hardware
USB-C (data)	1	Powered hub	Modern peripherals, data transfer
USB-C PD out	1	IP5389 board	Phone charging, 5V/??W

Starboard Side (Right, Facing Bow)

Networking + AV. "Plug in and leave" zone.

Port	Count	Source	Notes
Ethernet RJ45	1	OPi5 native	Gigabit, panel-mount extension
HDMI out	1	HDMI A/B switch	External display, switched from internal screen
3.5mm audio out	1	OPi5 native	Headphones, speakers, line-out

Bow Wall (Back Edge, Spine Side)

Power and cooling. No data ports.

Feature	Notes
USB-C power input	For IP5389 board charging
Fan exhaust grilles	Blowing away from user

Stern Edge (Front Edge, Lip)

User-facing. Clean for typing.

Feature	Notes
Carry handle	Stern-mounted per design decision
SD card reader	Panel-mount, for camera cards / quick imaging
Kensington lock slot	Physical security

Internal Components

Component	Connection
Powered USB hub (10-port)	Decased, wired internally. Feeds all USB-A and USB-C data ports.
HDMI A/B switch (mechanical)	Passive toggle. OPi5 HDMI in, two outputs (internal controller + starboard panel jack).
eDP-to-HDMI controller	Connected to A/B switch output A. Drives internal display.

Constraints

OPi5 has one HDMI output. The A/B switch selects internal or external — not both simultaneously.
DisplayLink USB graphics adapters do not work on ARM Linux (no drivers). Not a viable path for dual display.
Dual simultaneous display would require a different SBC (OPi5 Plus has 2× HDMI) or x86 board.
USB-C on the OPi5 is power-only in this build (consumed by IP5389 board). All USB data goes through the powered hub.

2.1 KiB Raw Blame History Unescape Escape