Any brave dive computer download testers out there?

Sébastien Dugué sebastien.dugue.subsurface at
Mon Apr 23 00:39:30 PDT 2018

On Sun, Apr 22, 2018 at 9:42 PM, Dirk Hohndel <dirk at> wrote:
>> On Apr 22, 2018, at 12:22 PM, Jef Driesen <jef at> wrote:
>> No, the protocol doesn't support that. But it does support downloading only the new dives. Unfortunately, the only way to take advantage of that is by means of the libdivecomputer fingerprint feature.
>> This is actually one of those cases where trying to implement the download only new dives feature entirely on the application side (without using the fingerprint feature) will always be inefficient. That's because the protocol works a bit different here. Unlike most other dive computers, it's the dive computer that does the work. You need to send a timestamp (of the most recent previously download dive) to the dive computer, and then the dive computer will only send back the newer dives.
>> The result is that if you don't use the fingerprint feature, then you will always request ALL dives And once you have all dives, you can ignore the ones you already had. But at that point you have already downloaded them all.
> I know we initially didn't use the fingerprint (5 or so years ago) because back then something was broken with it.
> Linus, is there still a design reason why we can't use it? Because that sounds like a HUGE inefficiency for dive computers like the G2 over BLE...

  Not only the G2. My Galileo and TEC 2G  both have the capability and
right now it's so long
downloading all dives before filtering the last few dives...


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