Re: hwOS Tech: 2.99 beta 5 released!
Date: December 05, 2018 09:16PM
this is to answer to the questions and remarks Llorenç put out some days ago:
1- New time-counter in compass personal view: it doesn't display the final digit of the seconds?
This is a bug, the second digit somehow gets lost while printing to the screen. It'll be fixed soon.
2- Exceeded MOD warnings for first gas not working properly. They doesn't seem to take into account the configured 'max ppo2 settings'... it seems that it uses a fixed 1.6 or use the 'max deco ppo2 setting' instead of the 'max ppo2 setting'. See images attached: max ppo2 = 1.4, max deco ppo2 = 1.6.... and the warning starts showing at 1.6, not at 1.4
While not in deco, an attention (color coding: yellow) will be given when the ppO2 of the current gas exceeds the ppO2 max threshold. In one of the pictures this happens with a Nitrox 32 at 38 meter yielding a ppO2 of 1,52 bar while in NDL, i.e. no deco. The color will change to red (warning level) when the ppO2 max deco threshold is reached (as seen in the other picture).
When in deco, the yellow attention will not be given - only the warning once ppO2 max deco is violated.
What actually still is a small bug or in-consequence is the fact, that the ppO2 values shown with the customs views omit the yellow color for the interval between ppO2 max and max deco and instead go directly from white (normal) to red. I'll align that with the color-coding as of above.
3-In some cases, Gas needs goes to 999 value. It doesn't occur always, but i've seen a couple of times during the ascent while going shallower than the first scheduled stop.
Argh, that seems to be a variant of a bug that was thought to be fixed already. In this particular case (current depth) - (depth of first stop) gives a negative number and that ruins the remainder of the calculation.
4- Minor commentaries: pressures readings/configurations related with the TR versions enabled by default
Yes, on purpose
... units of the surface pressure in hPa instead of mBar of previous versions.
Also on purpose, to give air pressures in Milli-Bar is officially revoked since quite a number of years, hPa (hecto Pascal) is to be used instead. The pressure number by itself is the same on both cases.
5- Better gas change (OC): in previous version, if you have an active deco gas with change depth set, once you arrive to this change depth the OSTC automatically suggested the change to that appropriate gas. In the new beta version, if you don't have deco stops at that depth, the OSTC doesn't suggest the change anymore at that depth... now it suggests it once shallower that the change depth, when you arrive at the first stop. For instance: nx50 deco gas with change depth of 21m... if the first deco stop is at 12m, OSTC won't suggest the change until you arrive at 12m. Also seems that gas needs calculations are made taking into account the change at the first deco stop (not the configured gas change depth)... i'm not sure if it does the same with deco calculations.
Well, two things: current diving situation and deco planning. As for the current diving situation, gas switch cues will be given as soon one is above the configured change depth of a gas and the ppO2 of the gas is not higher than the configured ppO2 max or max deco, dependent if in deco or not.
UPDATE: the above Statement is incorrect, gas switch cues are indeed given when arriving at the stop depth and this depth is at or above (shallower) the change depth of another enabled gas and the ppO2 of that gas will be within the set limits.
For the deco planning, the OSTC now assumes you won't stop your ascent just for the sake of switching your gas when you can also do that on the next "proper" stop some meters more up & just a minute or less later. It won't make a difference to the overall deco. You can make a switch on the fly if you want, on the other side if you're in a blue water ascent with buoy and reel, you'll probably do the switch once arrived at the stop, stabilized and the reel put on brake. The OSTC is just meant to be a tool to help you, it's not supposed to be a diving operations commander! :-)
The gas needs are calculated from the data in the stops table, so there is a direct dependency.
The only case where gas switches are placed deeper than the first stop is when an OC bailout from a CCR or pSCR dive is calculated. In this special situation the OSTC assumes your bottom B/O gas is limited and when there is a change to go to the next gas it should be done as soon as possible. Opposite to that, when ascending in an OC dive, the reserves in the back gas should be big enough to supply all the way up to the first real deco stop.
Edited 2 time(s). Last edit at 12/12/2018 05:55PM by Ralph.