Hardware Reference

Raspberry Pi

Model	Status
Pi 4B (8GB)	✅ Primary target
Pi 4B (4GB)	✅ Supported
Pi 5	⚠️ Untested
Pi 3B+	❌ USB 2.0 only

Storage / Boot Media

Media	Build Flag	Bus	Recommendation
A2 SD Card	`--target sd` (default)	SDIO	Dev/testing
USB 3.0 SSD	`--target usb`	USB 3.0	Portable use
NVMe SSD + HAT	`--target nvme`	PCIe	Production

NVMe HATs

HAT	Size	Price
Official RPi NVMe Base	2230/2242	~€15
Pimoroni NVMe Base	2230/2242	~€15
Geekworm X1001	2230	~€12
Geekworm X1002	2242/2280	~€15

USB SSD Considerations

Shares the USB 3.0 bus with audio interface — test for xruns under load
Self-powered USB 3.0 enclosure recommended
Run at 48kHz/128-frame buffer minimum

USB Audio Interfaces

Interface	I/O	Status
Behringer UMC1820	18/20	✅ Verified
Behringer UMC404HD	4/4	✅ Verified
Focusrite Scarlett 18i20 (3rd Gen)	18/20	✅ Verified
MOTU M4	4/4	✅ Verified
RME Babyface Pro FS	12/12	✅ Verified
Zoom UAC-8	8/8	✅ Verified
Behringer XR18	18/18	✅ Verified

Displays

Display	Connection	Status
Official RPi 7" Touch	DSI	✅ Verified
Waveshare 5" HDMI	HDMI + USB touch	✅ Verified
Waveshare 7" HDMI	HDMI + USB touch	✅ Verified

MIDI Controllers

All USB class-compliant MIDI controllers work. Tested with:

Behringer X-Touch One
FaderFox UC4
Arturia BeatStep Pro
Korg nanoKONTROL2

EEPROM Boot Config (Quick Reference)

# SD boot (default)
BOOT_ORDER=0xf41  # SD → USB → Restart

# USB SSD boot
BOOT_ORDER=0xf41  # USB → SD → Restart

# NVMe HAT boot
BOOT_ORDER=0xf614 # NVMe → USB → SD → Restart

See the Build-Instructions wiki page for detailed setup steps.