My Tempe sensor is connected to my Fenix 6 Pro but no data is received.

The watch will drop the connection unless you keep the widget active; as soon as it goes back into low power mode it drops all the ANT connections and shuts off that radio. So are you keeping the widget active or keeping an app open with your data field showing, but still never seeing the page 80/81/82 info? I feel an experiment coming on this evening. IIRC it's possible to send the Tempe a message to trigger the other messages, so wouldn't have to wait until the battery message finally arrives (as per my post above from three years back, that could be up to 129*3*2 seconds, in line with what you're seeing).

The battery info page is a common page so it's specced the same for all ANT devices, no reason why it shouldn't work unless the watch is requiring info which isn't actually compulsory to transmit.

My Fenix 6 definitely gave me battery low messages for the Tempe when it finally needed a new battery, so it must be paying some attention to the battery status even if it is in fact not showing it on the sensor page.

I think we're seeing the same thing. On my Forerunner 955, I just go to Settings/Sensors/TEMPE/About. And I only see dashes, or rarely a Battery value of OK. Often it'll be disconnected and I have to connect. So I think that is just an issue of the Watch disconnecting before the 13 min or so interval between pages 80/81/82.

However, on my EDGE 1030 when I run my data field, it'll continuously monitor and receive pages from the TEMPE. I get pages 0/1 every second, but pages 80/81/82 about every 13 minutes.

Curiously, I JUST started only getting page 75. I have no clue why. That is a "reserved" page with no explanation. I'll swap batteries and hope that is the issue. But until an hour ago it was working great. Oh, I get Battery Status (New, Good, Ok, etc). But the Voltage is INVALID (0x0F). Which is fine.

Well I'm intrigued by page 75. I guess we found the same documentation, common page reserved for future use as at 2016?

I've been playing with the ANT+ Display Simulator and my F7x simultaneously connected to my Tempe. It doesn't like it much (more stable when connected to only one or the other) but I have poked it to send pages 80, 81 and 82. The Simulator picks up all the data from 80 and 81, those fields just stay blank in the Fenix sensor About page. The battery status changes to OK when I request page 82, the Simulator displays battery Ok, battery voltage 16 which I think is what you're seeing, coarse battery voltage 15 and fractional battery voltage 255 being calculated as 15+255/256 and displayed rounded to two decimal places, rather than correctly shown as invalid. So yes I agree that it's not picking up tthe page 80 and 81 information.

The HRM manufacturer details and so on populate instantly, but HRMs don't use the common pages, they're coded differently. Same is true for bike speed/cadence. All that to say it looks as though the firmwares don't actually support reporting that info for the Tempe and is using per-device reporting for other units. 

I'm not sure I'm all that bothered, I don't think the Tempe can update firmware anyway; the key information is the battery status and that works if you wait long enough (and will be picked up by the watch if you're logging the Tempe during a ride/run/whatever). The Edge units don't have the same low power mode with watch face/notifications only that the watches do so it makes sense that i would stay connected continuously, and the data field would work the same way on your Fenix as it stays out of low power mode while it's in an activity (I'm sure you understand all this, just amplifying for other folk browsing the thread).

Interesting chat though and nice work on the data field!

You know this stuff better than I do... but here is what I'm seeing.... every time I open the channel I get this sequence of pages from onMessage. Then I start to get pages 0 & 1 every second, and pages 80/81/82 only every 13 mins or so. I'm not sure where these are coming from or why, but these are not BROADCAST pages. So I can just ignore these. Anyway, that was where Page 75 was coming from... so nothing to see here :-)

Here is a burn test. Counts of the various broadcast pages I see. Resets are when I run into this and set "searching = true". I set a -2F offset to manually calibrate the TEMPE. I put in a brand new battery and still get OKAY, so I'm thinking that is fake and static.

Yup I think the Tempe only transmits OK and Low - as I say I have seen watch messages saying the battery is low - but no more specific than that.

I don't know what the messages in your previous post are - a couple of them look like ANT file system messages, which is according to the spec how Tempe can receive current time. The message 0 values I see suggest it can receive UTC times, the display simulator doesn't send them by the look of it. The other thing that could be going on is messsages about the Tempe adjusting its transmission power once it's connected. I haven't found any documentation on how that's transmitted but I see these reports:

Device Sent Capabilities Info [this is probably just the message 0]
Device Changed Transmit Power

OMG, did you know that a tempe only transmits once a minute?   Hey guys, have you ever thought about adding the temperature data field to your activities? It's a game-changer! Trust me, tracking the temperature during your workouts or outdoor adventures can give you so much insight into your performance and help you optimize your training. Give it a try and let me know how it goes! If you're wondering about using the internal temperature sensor, I've got you covered! 

Yes - I wrote a data field that gathers temperature from a variety of sources. Device Temp, Live Weather, and TEMPE. It uses logic to try to determine the best source. For example, Live Weather is not good when riding indoors (in the A/C or a Heated House). But for me, with many Weather Stations, and no elevation change in Florida, Live Weather is best outdoors. I allow the User to select from among LIVE, DEVICE, TEMPE, or USER. Device Temp can be skewed from sun exposure, and TEMPE is often a couple degrees off and needs a manual offset. It has been interesting working out all the details. I use this to inform an athlete on the amount of hydration they should be consuming, which is influenced by temp, elevation and effort. Once a minute is more than frequent enough... temps don't change that fast :-) Well, they can on a fast descent down a mountain (elevation change, often 3.5F per 1000 feet), but for my use, real-time hydration consumption rate, that resolution on temp tracking is fine.