FTMS message for "Set Targeted Cadence"

Bugs and Support
1

Hi,

I’m working on a DIY smart trainer, and I have a mode where the trainer can “pedal by itself” to test it out. When doing a workout that specifies a target cadence, I do not receive the “Set Targeted Cadence” message defined in the FTMS spec. Here is the relevant bit in the spec:

4.16.2.21 Set Targeted Cadence Procedure
This procedure requires control permission in order to be executed. Refer to Section 4.16.2.1 for more information on the Request Control procedure.
When the Set Targeted Cadence Op Code is written to the Fitness Machine Control Point and the Result Code is ‘Success’, the Server shall use the value sent as a Parameter as the new targeted cadence.
The response shall be indicated when the Set Targeted Distance Procedure is completed using the Response Code Op Code and the Request Op Code, along with the appropriate Result Code as defined in Section 4.16.2.22.
If the operation results in an error condition where the Fitness Machine Control Point cannot be indicated (e.g., the Client Characteristic Configuration descriptor is not configured for indication or if a procedure is already in progress), see Section 4.16.3 for details on handling this condition.

Is there a specific reason Zwift does not send this FTMS message when there is a target cadence set in the workout?

Thanks,

Patrick

2

I suspect there are no smart cycling trainers that actually implement this as it implies that the trainer would either force the cyclist to pedal at a certain cadence (sounds painful) or display it in a UI so the cyclist can match it. Maybe something that would be used by a fitness cycle that has a display for the target cadence? Fitness games like Zwift already have a UI for the target cadence so I would guess they don’t need this.