Twinleaf Serial Sync Differential (SSD) Link
NB: As of 2025, SSD links are deprecated in favor of the TDS link.
Physical interface
Many Twinleaf devices prior to 2025 provide an 8p8c (RJ-45) connector for serial communication, power delivery, and synchronization called the SSD connector.
The pinout is:
| Pin | Signal | Wire color |
|---|---|---|
| 1 | TX+ | Orange/White |
| 2 | TX- | Orange |
| 3 | RX+ | Green/White |
| 4 | +5V | Blue |
| 5 | Ground | Blue/White |
| 6 | RX- | Green |
| 7 | SYNC+ | Brown/White |
| 8 | SYNC- | Brown |
| 9 | Shield | (Braid) |
TX is data sent to the sensor. RX is data received from the sensor.
The wire colors correspond to the colors found in standard ethernet or CATx cable. Standard ethernet cables are appropriate. The serial port uses 3.3V LVDM, a differential signaling format that can be converted to RS-232 or LVTTL for microcontrollers using an LVDM or LVDS PHY chip. The data rate is 115200 (N81). We provide a SSD-USB converter dongle with all sensors that do not also have a USB-C port.