Cadence data sent out under the umbrella of GT key?

Post Reply
Zoltan
Posts: 213
Joined: Mon Jan 23, 2012 9:47 am
Location: HUNGARY

Cadence data sent out under the umbrella of GT key?

Post by Zoltan »

Is it possible that when I use my iAero Gen3 for sending power data to my Garmin, it also transmits the cadence data?

I know my question is strange, but a YES answer would explain something strange I am experiencing.
Velocomp
Velocomp CEO
Posts: 7793
Joined: Fri Jan 11, 2008 8:43 am

Re: Cadence data sent out under the umbrella of GT key?

Post by Velocomp »

No. GT enables iBike power sending information. It has nothing to do with cadence.
John Hamann
Zoltan
Posts: 213
Joined: Mon Jan 23, 2012 9:47 am
Location: HUNGARY

Re: Cadence data sent out under the umbrella of GT key?

Post by Zoltan »

Thanks for the confirmation, which was the logical answer.

OFF
For those who also have Edge 705 apart from iBike with a separated ANT+ cad sensor and an ANT+ spd sensor instead of having a cad/spd combo sensor, I have an experience.

I have a speed sensor and a cadence sensor on my trekking bike.

So I set YES in Settings/ANT+ Sport/Accesories/Cadence on my Edge 705.

I did not expect to get cadence on Edge, because I had read that it requires an ANT+ (combo) spd/cad sensor (maybe I’m wrong concluding it), and indeed it was not shown on my Edge 705. My cadence sensor is perfect, my other gadgets including iAero were able to show the cadence.

Although cadence was not displayed on Edge 705, surprisingly I realized at home that there was cadence data in the .tcx file.

Is it the same for everybody having separated spd and cad sensors?

ON
texmurphy
Posts: 122
Joined: Fri Jan 29, 2010 4:16 pm

Re: Cadence data sent out under the umbrella of GT key?

Post by texmurphy »

Velocomp wrote:No. GT enables iBike power sending information. It has nothing to do with cadence.
I disagree!

I have had a low-voltage gsc-10 which would detect cadence but not speed. This is a known result of gsc-10 low battery where the gsc-10 will continue to report cadence but fail on speed. I set my Edge 500 to disable the gsc-10 so that it would produce speed from gps only. The configuration then being iBike Gen III Pro with Garmin key, Edge 500 without speed/cadence sensor. The Edge 500 does not broadcast either speed or cadence, so the iBike did not detect motion due to the low gsc-10 battery.
I may be able to locate the iBike and Garmin data if there is any interest.

However the iBike Gen III Pro did broadcast Cadence to the Edge 500. This happened on a ride several years ago, but I distinctly remember thinking it would be nice if the iBike also broadcast speed (like most ANT+ DFPM's) since there are some problems with the way the Edge 500 determines change in speed to halt (moving to a stop).
It may be the Newton does not broadcast Cadence, but broadcast of Cadence and Speed (maybe Elevation but I don't know if ANT+ supports that) would be a nice enhancement :D

Zoltan - simple test, disable the gsc-10 on the 705 and see if you get cadence from the iBike and speed from the 705 gps. I may do a test soon on my Newton.
Velocomp
Velocomp CEO
Posts: 7793
Joined: Fri Jan 11, 2008 8:43 am

Re: Cadence data sent out under the umbrella of GT key?

Post by Velocomp »

texmurphy wrote:
Velocomp wrote:No. GT enables iBike power sending information. It has nothing to do with cadence.
I disagree!
We're fine with disagreements, but facts are facts...

The way it works is this: sensors, such as the GSC-10, are ANT+ transmitters. Transmitter sensors broadcast their ANT+ data to ANT+ receivers, such as the iBike. Once paired, the receiver captures the data broadcast by the transmitter.

The iBike is a receiver of speed, cadence, speed/cadence, and DFPM signals broadcast by ANT+ sensors. The iBike NEVER re-broadcasts data received by ANT+ transmitters; it is incapable of doing so.

The GT key enables the iBike to transmit its power signals. Effectively, the iBike becomes a transmitter of power signals. Then, any other ANT+ receiver, such as a Garmin, can receive the iBike power data.
John Hamann
Zoltan
Posts: 213
Joined: Mon Jan 23, 2012 9:47 am
Location: HUNGARY

Re: Cadence data sent out under the umbrella of GT key?

Post by Zoltan »

texmurphy wrote:
Zoltan - simple test, disable the gsc-10 on the 705 and see if you get cadence from the iBike and speed from the 705 gps. I may do a test soon on my Newton.
I do NOT have gsc 10, just a separated cadence and a separated speed sensor. Actually this is what I did, I disabled the cadence sensor on Edge 705 (note: no speed sensor activation on Edge 705, just HR, cad and power, since cad should mean a spd/cad combo sensor), but I got cadence also for that streach of my ride. It is why I raised my question, because there could be two reasons.

1) iBike transmitted the collected cadence to Edge 705, not just Power, I mean some stream of cad/power.
2) my Edge 705 always collects cadence data even if the cadence settings is "NO".

Since option 1 was uncomfirmed by Velocomp, I have to accept option 2.

And I am quite sure there is someting with my Edge 705, since it is more than suspicious that it dispalys cadence as "---" meanwhile in the background it is collecting cadence data from some source and writes it finally into a .tcx file.
User avatar
racerfern
Posts: 1356
Joined: Fri Jan 11, 2008 12:47 am
Location: Baldwin, NY
Contact:

Re: Cadence data sent out under the umbrella of GT key?

Post by racerfern »

So leave the cadence sensor disabled within the 705 settings and do not turn on the iBike. See if the cadence is recorded but ignored.

FWIW I do not trust the settings in the 705 as far as using or not using SPD or CAD sensors.
Fernando
Zoltan
Posts: 213
Joined: Mon Jan 23, 2012 9:47 am
Location: HUNGARY

Re: Cadence data sent out under the umbrella of GT key?

Post by Zoltan »

racerfern wrote:So leave the cadence sensor disabled within the 705 settings and do not turn on the iBike. See if the cadence is recorded but ignored.

FWIW I do not trust the settings in the 705 as far as using or not using SPD or CAD sensors.
Definitely it will happen, but these days I am too busy at work to go for an immediate ride. Moreover the test should be done on both bikes, since my PT hub maybe behaves like a cad sensor, too.
Velocomp
Velocomp CEO
Posts: 7793
Joined: Fri Jan 11, 2008 8:43 am

Re: Cadence data sent out under the umbrella of GT key?

Post by Velocomp »

Zoltan wrote:
racerfern wrote:So leave the cadence sensor disabled within the 705 settings and do not turn on the iBike. See if the cadence is recorded but ignored.

FWIW I do not trust the settings in the 705 as far as using or not using SPD or CAD sensors.
Definitely it will happen, but these days I am too busy at work to go for an immediate ride. Moreover the test should be done on both bikes, since my PT hub maybe behaves like a cad sensor, too.
Yes, your PT hub transmits cadence data, too.
John Hamann
Zoltan
Posts: 213
Joined: Mon Jan 23, 2012 9:47 am
Location: HUNGARY

Re: Cadence data sent out under the umbrella of GT key?

Post by Zoltan »

But the data should not be received by Edge 705, when cadence is disabled and only HR and power are enabled.
Post Reply