Incorrect tank info.

[Jef Driesen]

On 2012-08-23 17:18, Lutz Vieweg wrote:
> On 08/23/2012 05:05 PM, Jef Driesen wrote:
>> BTW, what about the case where you set your gasmix to nitrox, but 
>> the decompression algorithm to
>> air?  That way you use the nitrox for an extra safety margin 
>> (because the deco algorithm is using
>> air), while the actual mix is still used for calculation oxygen 
>> toxicity. Or doing just the
>> decompression with a richer mix, and keep the dive computer on air. 
>> Again no idea if the Suunto's
>> support this.
>
> The Sunnto D4/6/9 computers do not support that.

What exactly happens if you set the device to air mode? Can you still 
configure the gasmixes, or is access to the gasmix settings completely 
disabled? I'm just trying to understand the logic used by the device. 
Then we can fix the libdivecomputer code to match that logic.

Based on the comments so far, this seems to be what is happening:

if (air) {
    Ignore the gasmix settings, and assume a single mix with air. The 
gasmix settings retain their previous (non-air) values only as a 
convenience, so you don't have to adjust the settings for your next 
nitrox and/or multigas dive, but they are not used.
} else {
    Use the gasmix settings.
}

>> If you have the list of gasmixes, you can easily tell apart whether 
>> it's an air, nitrox or mixed gas dive
>> (or trimix, heliox, or whatever you like to call it).
>
> But if Suunto does not report 21% O2 for "Air Mode" dives, it would
> still be good if libdivecomputer
> could detect the mode and work with 21% O2 anyway.

Of course. It just happens to be that my initial assumption (e.g. 
gasmix settings matches the dive mode) was wrong. Nobody complained so 
far, so I assumed it was correct :-)

Jef