Servo BUS editor

The Servo BUS editor lets you define or edit a serial servo connected via D4C (DEIMOS) protocol (e.g. Waveshare ST3215 / ST3215HS). It opens from the start window → Elements tab → New or Edit button, selecting the Servo BUS type.

Main fields

Field	Description
Name	Unique servo identifier in the domain (e.g. "Head", "Mouth"). Required.
Description	Free notes about the element (optional).
Type	Set to Servo BUS. Can only be changed at creation time.
Port	Domain serial port where the BUS chain is connected (e.g. COM3). Must use D4C (DEIMOS) protocol.
Color	Track color in the timeline. Click to change.

BUS profile

Field	Description
BUS ID	Unique address of the servo on the serial chain (1–253). Must match the ID programmed in the servo firmware. Required.
Model	Servo model: ST3215 or ST3215HS. Determines available speed and acceleration limits.
Initial position	Position in degrees (0–360) the servo moves to when the port is opened and when playback ends.

Advanced options

Click the Advanced options button to access movement parameters:

Field	Description
Speed	Default maximum movement speed (hardware units). Range depends on model: ST3215 = 0–3500, ST3215HS = 0–7500.
Acceleration	Acceleration/deceleration profile (0–150). Higher values = smoother movements.

Movement limits

Field	Description
Minimum limit	Minimum angular position allowed during playback (0–360°). Mechanical protection against out-of-range movements.
Maximum limit	Maximum angular position allowed during playback (0–360°).

Always set min/max limits within the physical range of your servo and mechanical installation. An out-of-range movement can damage the mechanism or tear cables.

Common errors

Message	Cause and solution
BUS ID not set	The BUS ID field is 0. Enter a value from 1 to 253 matching the servo ID.
Name already exists	An element with the same name already exists. Use a different name.
Duplicate BUS ID	Another servo on the same port already uses that ID. Each servo on the same chain must have a unique ID.