External Connectors
MDD400 v2.9 — Fabricated prototype — testing phase
| Connector | Style | Domain | X (mm) | Y (mm) |
|---|---|---|---|---|
| NMEA 2000 | M12 A-coded 5-pin (Micro-C) | CAN | −16.0 | 0.0 |
| ESP-PROG Programmer | IDC 6-pin Male 2.54 mm pitch | DIGITAL | 12.0 | −17.5 |
| HMI Display FFC | 50-pin 0.5 mm FPC top/bottom clamshell | DIGITAL | 10.0 | −10.0 |
| Legacy Serial / NMEA 0183 | 3-pin Autohelm-style connector | LEGACY IO | 29.0 | 10.5 |
X and Y are PCB-frame coordinates of the connector's reference point. For pinouts and electrical detail see CAN Transceiver, Programming Socket, Display Interface, and Legacy Serial Interface.
NMEA 2000 connector pinout
The NMEA 2000 network connection (J2) is a 5-pin M12 A-coded (Micro-C) male panel-mount connector. The diagram shows the pin assignments viewed from the front (mating face) of the device connector.
| Pin | Signal | Description |
|---|---|---|
| 1 | Shield | Cable shield / drain — left floating inside the device (NMEA 2000 practice) |
| 2 | NET-S | Power supply positive (+V) |
| 3 | NET-C | Power supply common (−V) |
| 4 | NET-H | CAN-H |
| 5 | NET-L | CAN-L |
ESP-PROG programming header pinout
The programming socket (J1) is a 2×3 IDC header following the Espressif ESP-Prog "Program" convention. Full circuit detail is on the Programming Socket page.
Legacy serial connector pinout
The legacy serial connector (J3) is a 3-pin Raymarine-compatible connector. See the Legacy Serial Interface page for the isolation and signalling detail.
Rear connector panel
The faceplate decal on the rear face of the MDD400 housing, showing the connector layout as installed: the NMEA 2000 socket (J2), the ESP-PROG programming header (J1), the legacy serial connector (J3), and the status-LED window — alongside the product marking, compliance marks, and documentation QR code.
