deco with inactive gas

[stryke]

Hi,

When using a inactive deco gas, when validating the gas:
- Before: The deco plan was recalculated immediately
- Now: The deco plan starts from the current value and decrements

Is there an option for the plan to recalculate immediately?


What is the option in the deco menu (in French) "Palier + long"?

[Ralph]

Hi,

can you help me a bit with what you mean by "The deco plan starts from the current value and decrements"?

Basically you can pick any gas from the menu - including disabled gases - and the OSTC will use it, that is will assume you are breathing this gas and will do the calculations accordingly. Anyhow, the deco calculation will continue looking for better gases and may prompt at you to switch back to some other gas. If you don't want a specific gas to be used by the deco calculation, you have to tell the OSTC by setting the respective gas to the 'lost' state via the gas menu, 3rd page.

Regarding "Palier + long" - can't find it in the language file. Are we both speaking of the HWOS Tech or latest Sport firmware for the 2, Plus, TR or cR model?

[stryke]

Hi Ralph,

Example: Air Diving and I activate a deco gas (98% O2) at the end of the dive

Be careful the deco values below are just to understand

Before: DTR Air 20mn, I activate the deco gas and immediately the OSTC displays the new DTR 12mn (example)

Now: DTR Air 20mn, I activate the deco gas and the OSTC does not immediately recalculate the DTR but counts down 20, 19, 18, etc ...
The minutes are not real minutes the count at the beginning is very fast.

In the end the deco time is the same as if you activate the deco gas before diving (test done on a dive with 2 OSTC)


For the second point, firmware HWOS Tech in French
Menu > Menu Deco > Paramètres Déco > Suite > Paliers + Longs

[ClaudeDive]

Hi Ralph

"Paliers + Longs :" corresponds to the function> TCODE tExtendedStops

Kind regards

[Ralph]

Well, "extended stops" function does, what "extended stops" in MultiDeco does, too: if enabled, gas changes are prompted for and also assumed in the deco calculation to be done as soon as a better gas becomes available (by changed depth and ppO2 threshold). If disabled, the gas change will be delayed until the next deco stop is reached, i.e. there will be no gas changes "on the fly".

For the other question about TTS behaviour, i will need to have a deeper look into it. I will come back on you...

[Ralph]

Hi again,

>When using a inactive deco gas, when validating the gas:
> - Before: The deco plan was recalculated immediately
> - Now: The deco plan starts from the current value and decrements

I can confirm your observation, good job! When looking at the gas needs calculation results, one can see that the deco forcast (TTS) does not take into account the manually selected disabled gas, but sticks to the best one out of the enabled gases. The tissues itself are updated with the true selected gas, that's why in the end the deco clears according to the selected gas. I will fix that...

BR
Ralph


UPDATE: the fix is coded, will ship together with the reworked initial ascent calculation as soon as all tests have finished.

[stryke]

Hi Ralph,

Thanks a lot