Multibay

MultiBay USB3 HDD adapter (PATA + SATA)

Desk/cable adapter: USB 3.0 Type-B upstream, 2× SATA (2.5"/3.5"), 40-pin + 44-pin PATA on one ATA channel, 12 V barrel + Molex. Aimed at JLCPCB (4-layer impedance) + LCSC SMT.

v0.2. Pad-to-pad copper, USB3 hub TX→bridge RX through 100 nF, PATA bus to both IDCs, inner-layer planes only (no shorting F.Cu flood). SuperSpeed is still not TDR-lab verified. USB2 fallback is possible on the first spin.

USB3-B ── VL817-Q7 hub
            ├─ ASM1153E → SATA A
            ├─ ASM1153E → SATA B
            └─ ASM1153E → JM20330 (device bridge) → IDE 40 + IDE 44
12 V DC (centre+, 8–10 A brick) → 12 V drives + 5 V buck → logic / 2.5"

SPECTATOR (this workstation)

SPECTATOR: xmux attach multi-hdd-pcb --no-reconnect

One Xmux session (multi-hdd-pcb, 1600×900). Preview: hardware/multibay/preview.svg. Do not maximize the viewer (known black frame).

Fab-ready goal (multi-agent, does not end early): docs/GOAL-FAB-READY.md — run /fab-ready or /workflow fab-ready.

Order in China (JLCPCB)

Files in hardware/multibay/:

PCB cart: 4-layer, 1.6 mm, ENIG, impedance control, stackup JLC04161H-3313. USB 90 Ω (0.20/0.15 mm), SATA 100 Ω (0.15/0.20 mm). Not fab-ready until docs/GOAL-FAB-READY.md MUST gates are green (KiCad shorting_items=0).

Reputable houses: JLCPCB (primary), PCBWay, Seeed Fusion.

THT (USB-B, SATA, IDE, DC jack, Molex, radials): hand-solder or JLC THT. JM20330 is not on LCSC — buy TQFP-64 and place by hand, or DNP U5 and use an external SATA↔IDE dongle on the SATA-C pads.

Power brick (not on the PCB): 12 V centre-positive 5.5×2.1 mm, 8–10 A.

Native generate (no AppImage / Flatpak)

Root /usr is too full for a KiCad install. This repo does not need KiCad to produce Gerbers.

source /mnt/python/bin/activate   # or any Python 3.11+
make hardware                     # → hardware/multibay/
make test                         # pytest
make verify                       # connectivity + pair-length; ngspice if /mnt/ngspice exists

CLI (python -m pcbgen):

python -m pcbgen -h
python -m pcbgen -v
python -m pcbgen -o hardware/multibay

No-args prints usage. -v is version (not verbose). Gerbers on by default; --no-gerber / --no-kicad disable those exports.

Optional GUI/autorouter (prefix-built on /mnt, not /usr):

source /mnt/pcb-tools/env.sh
kicad-cli -v          # after KiCad install
freerouting -h
qucs-s --version
ngspice --version

See docs/pcb-tools.md. Do not use AppImage or Flatpak on this box.

Ports (your drives)

• 2.5" HGST 44-pin PATA → J7
• IBM DJNA-352500 3.5" 40-pin PATA → J6 (same channel; M/S/CS on JP1)
• Extra SATA SSDs/HDDs → J4 / J5

Layout of this repo

Honesty

USB 3 + SATA PHYs on a first-pass 4-layer board are the risk. Power distribution and PATA wiring are the easy parts. Budget a respin after lsusb / a SATA SSD smoke test.