Status: Accepted, amended by ADR 0069 (silent: is deprecated) · Recorded: 2026-11

Context

An execute frame in the 8-byte form ends in a speed profile byte. The hub sends 06 on every position move to a kind that takes that form, and 05 for silent: true: the two values a Somfy hub sends for a normal and for a silent move. A VELUX controller sends neither. A KLR 200 control pad moves a window with the 6-byte form, 01 63 C8 00 00 00 for a close, which carries the main parameter only.

On a VELUX roof window the three frames give three speeds. A full travel of one window, measured in issue #205: 44.5 s from its pad, 26.5 s on profile 06 and about 65 s on profile 05. So the hub moved the window at its fast speed, audibly louder than the pad, and a window driven by both moved at two speeds. The VELUX KLF 200 API names three velocities for a command, DEFAULT (0), SILENT (1) and FAST (2); 05 acting as SILENT and 06 as FAST fits them.

silent: is a boolean, and its switch chooses between 05 and 06. Nothing chose the 6-byte form.

Options considered

Send the 6-byte form to every VELUX window. Rejected: a cover declares no maker, so nothing tells a VELUX window from another, and the fast speed is one some users want.
Make silent: three-valued. Rejected: a boolean key that also takes a string, and a switch that would have to become a select, changing the entity of every config that has one.
Send profile 04 for the motor's own speed, the KLF velocity 0 with the offset 05 and 06 share. Not chosen: nothing has been captured with it, while the 6-byte form is what the pad sends and what was measured.

Decision

travel_speed: takes default, silent or fast on a cover whose kind takes the 8-byte form, the same gate as silent:. fast sends profile 06, silent profile 05, and default the 6-byte main-parameter frame that create_execute_main_parameter() already builds for kinds without the 8-byte form.
Without the key the hub sends what it sent before: profile 06, or what silent: says. silent: stays as the two-way form of the same setting: true is silent, false is fast. A cover takes one of the two keys.
Declaring the key generates a <Cover Name> Travel Speed select with the three options, and the YAML value is its boot state, as for the Silent Operation switch. The device holds a TravelSpeed in place of its silent flag. The enumerator for the motor's own speed is MOTOR_DEFAULT, not DEFAULT, which the Arduino core defines as a macro on some targets.
The speed shapes position moves, open and close included. The favorite position keeps its 6-byte frame except on silent, as before. Stop, force open, ventilation and tilt are unchanged.

Consequences

No existing config changes behaviour or entities.
A VELUX window can move at its pad's speed, and then moves alike from the pad and from the hub.
What default does on other makers' motors is unmeasured. Kinds without the 8-byte form already get the same 6-byte frame for every move, so a motor is expected to accept it.
Like silent:, travel_speed: is a declared preference: the select shows what the hub sends, not a reading from the device.