New firmware 2.27beta

[heinrichsweikamp]

Hi,

Again:
- Don't use the OSTC for depths >120m
- As a warning the depth will be red (Default setting) at 120m
- The pressure sensor works up to 14bar absolute
- We can't change the sensor using a firmware update

Sorry if this is not the answer you want to read.

Cheers,
Matthias

[milkyway]

Hello!

@DiverM
Thanks for your work. Is it possibe to get a file for the German language?

Thx in advance.

CU Oliver

[DiverM]

milkyway Wrote:
-------------------------------------------------------
> Hello!
>
> @DiverM
> Thanks for your work. Is it possibe to get a file
> for the German language?
>
> Thx in advance.
>
> CU Oliver


Yes, it is possible to compile a version in German. But as it is, v2.21 stable is already available in german, and with the v2.27 beta you shouldn't dive. And as far as testing goes, you might as well test it with the english version as the language does not alter the behaviour of the software.

When the next stable is realeased I can compile it in all available languages with the safety stop depth and or time changed for 6-3m.

[milkyway]

Hello!

@DiverM
Thx for your reply. With the beta-software I shouldn't dive, that's clear - but I'll do this (with a backup TC - Sol) just to test the new features.

Of course, it's not a problem to do this with the english version (I speak a famoust accent without the slighest english), but only to increase my own comfort it would be nice to have it in the German language.

So if it's not a hard work for you.........

CU Oliver

[heinrichsweikamp]

Hi,

The beta zip: http://www.heinrichsweikamp.com/#/de/ostc_2n/firmware/ contains a version in German (mk2_v227-beta_deutsch.hex)

Edit: Never mind. I think you referenced to the custom build...
Regards,
Matthias

[milkyway]

Hello!

@Matthias
Yepp, you're right.

A safety stop from 6 to 3m is nearly perfect for me.

CU Oliver

[Solodiver]

heinrichsweikamp Wrote:
-------------------------------------------------------
> Hi,
>
> Again:
> - Don't use the OSTC for depths >120m
> - As a warning the depth will be red (Default
> setting) at 120m
> - The pressure sensor works up to
> 14bar absolute
> - We can't change the sensor using a firmware
> update
>
> Sorry if this is not the answer you want to read.

I'm pretty sure we've discussed this and have for sure seen a copy of the part of the source code which shuts down the unit. The question is still why is this there? I and others only ask to remove this part of the software, not to change/update the hardware specifications.

And to make it clear (again, also discussed before): The DR5 is not an alternative (for me)! Know to much guys which have too much trouble with these units and I also tested it myself and found it not comparable to the OSTC, Sorry. The OSTC is advertised as a technical dive computer and at least in these advertisements there is nothing found about this limit. 130m is not out of reach for nowadays divers and will be normal as CCR diving will become even more popular. I'm pretty sure I've discussed this question before I bought the unit (and the DR5 also has been an option) and have been told, that the only issue is the deco model which is not made for dives deeper than 120m. As this is also true for Shearwater and any other unit not having these depth limitations it is fine for me knowing this when using the unit deeper (intended or accidentally), especially as it is my backup unit. But a dead unit is not acceptable at all, so I ask again to remove this limitaion, thx.

Lets try it this way: Is there any difference if the unit is switched off or running at a depth of 150m?

Update: As it may not be clear for others not following the discussions before: We've been told that the depth sensor is not working _accurately_ for more than 14 bar, meaning the shown depth (and used for deco calculations if applicable) could (will) drift away from the real depth. This is an different statement from "working up to 14bar" as seen above. As I understood, the same sensor is also built in to the DR5 accompanied by an 2nd sensor for reading greater depth (but not reliable at shallow areas).

Thx,
Jan

[heinrichsweikamp]

Hi Jan,

Please look at the facts (See datasheet DA5541C_005) again, the sensor (MS5541C) is guaranteed to work up to 14bar (Which is about 130m). In other computers other sensors may be in use (There are sensors for more then 14bar).

Will the ADC in the sensor clip or overflow at 140001mbar? Will it work up to 15bar? Even with all Cx-values at it's max. or min. allowed value (See AN518)?

If you are sure about the consequences just remove the error-routine by yourself or find someone doing it for you. We won't do that, sorry. This lock-out is intend to catch sensor errors - a non-working computer may be safer then a unit showing wrong information.


> diving will become even more popular. I'm pretty
> sure I've discussed this question before I bought
> the unit (and the DR5 also has been an option) and
> have been told, that the only issue is the deco
> model which is not made for dives deeper than
> 120m.

Definitely not. It's stated very clear in the OSTC manual or in our Flyers and if you have have asked us you've had been told that the unit is workable for dives up to 120m and shows depths until 130m.

As this is also true for Shearwater and any
> other unit not having these depth limitations it

Which sensor is used in the Shearwater?

regards,
Matthias

[Chilihead]

Pursuit V68 Manual

• Transducer depth range: 14ATA
• Transducer depth accuracy: +/-2.5%

Predator Manual v2.3.3 (English)

Transducer Depth Range: 14ATA
Transducer Depth Accuracy: +/- 2.5%

The OSTC Pressure Sensor - MS5541C
• Pressure range 0 - 14 bar

May be the Same Sensor??

ok... the Shearwater Pursuit @ 500m works...

[tiefunten]

The datasheet of the OSTC Sensor only states, that it can withstand an absolute pressure of 30 bar in salt water - but it is written nowhere, how it behaves at higher pressures than 14bar.

Matthias, did you check this behavior (of the sensor) below 130m in your pressure pot? For me, the depth range of the OSTC is absolutely sufficient, but it would be interesting to know...

[Solodiver]

Thx Matthias for clarifying. I just checked my mails and found a message related to the depth from Christian some years ago but relating to the DR5. Sorry, got this mixed in my memories or got to much inert gas bubbles in my brain.

heinrichsweikamp Wrote:
> a
> non-working computer may be safer then a unit
> showing wrong information.

This is exactly my point from the opposite direction. Why do you think this is? In my opinion a non working unit is useless, so why force one to loose even time information and also depth when ascenting above -130m? Why not switch the unit to Apnoe mode then, switch it off temporally or just make very clear that the given information might (!) be wrong (I prefer the latter one). The unit is meant for experienced divers and in such depths for sure used together with other dive computers as well, so there is and should be redundancy. Personally I'd trust the OSTC more than the Shearwater and would really like to keep this unit! We have CF for everything, why not for such a very, very critical part!?

Thx guys for coming up with the sensor specs for the Shearwater, looking forward to get this topic discussed finally. Should we move this to a new, separate thread?

Thx a lot,
Jan

[scubatinoo]

This part of the discussion enforces my conclusion that OC and CC should be separated into to two different computers - or at least two different firmwares...

[swissdiving]

DR5

[heinrichsweikamp]

Solodiver Wrote:
> > non-working computer may be safer then a unit
> > showing wrong information.
>
> This is exactly my point from the opposite
> direction.

Don't worry - we understood your point (You have posted it enough times now) but we won't change this due to reasons that have been discussed here in detail.

Cheers,
Matthias

[cparsons]

I have been following the discussion(s)about the 130m limit - and totally agree that if the sensors are rated to 120m (as well as the decompression calculations) then it seem sensible not to ignore this?

However, if anyone does not agree with this, why do they not simply disable this shut off in the code and recompile?

From a personal point of view I would not want a CF that allows me to exceed the hardware limits, if the sensor is passed it's limit do you _really_ know if the readings it is giving are accurate (at all!) or that it will not just cease working altogether (meaning a replacement OSTC I guess as the hardware is encapsulated?)

I don't want to upset anyone but as the firmware is open source you can make your own decision surely?

Be safe

[swissdiving]

I would think for HW there is also a legal dimension to this issue. Especially in the markets outside Europe.

[scubatinoo]

swissdiving Wrote:
-------------------------------------------------------
> I would think for HW there is also a legal
> dimension to this issue. Especially in the markets
> outside Europe.

Thinking about legal dimension it becomes interesting that this kind of limitations can be overwritten by everyone...

[DiverM]

scubatinoo Wrote:
-------------------------------------------------------
> swissdiving Wrote:
> --------------------------------------------------
> -----
> > I would think for HW there is also a legal
> > dimension to this issue. Especially in the
> markets
> > outside Europe.
>
> Thinking about legal dimension it becomes
> interesting that this kind of limitations can be
> overwritten by everyone...

The CE marking is ony valid with vendor supplied software, or vendor approved software. Thus a legal discussion about this will be very short.

Same story for any custom firmware I have compiled , and will be compiling is the future. Using it for testing is fine, trusting on it for diving is not.
That said, the changes are minimal, and should not affect the performance of the computer as used with normal stable firmware. Nevertheless, if you use it, make sure you have backup instruments and tables! Plan your dive and dive your plan!

[swissdiving]

[quote=DiverM]
The CE marking is ony valid with vendor supplied software, or vendor approved software. Thus a legal discussion about this will be very short.
[/quote]

Thats exactly my point. I would think HW couldleave itself open to a lawsuit if they would release and/or approve a SW version with the limitation removed.

If someone else wants to do this for their own unit. Go for it.

[Solodiver]

> swissdiving Wrote:
> --------------------------------------------------
> -----
> > I would think for HW there is also a legal
> > dimension to this issue. Especially in the
> markets
> > outside Europe.

I would start a lawsuit if I found one of my buddies dead wearing a shut down divecomputer finding out it has been switched off by purpose by the software running on it...

Just my EUR 0,02

[scubatinoo]

What's the difference between a switched off unit and an unit that produces nonsense data because it's out of the limits - when you're dead?

[heinrichsweikamp]

Solodiver Wrote:
> I would start a lawsuit if I found one of my
> buddies dead wearing a shut down divecomputer
> finding out it has been switched off by purpose by
> the software running on it...


Please re-read my post from "July 15, 2012 10:27AM", ask specific questions if you don't understand the facts mentioned there.

And stay on topic, thanks!

Regards,
Matthias

[smcmullan]

Hi Matthias,

The only reference I can see in the OSTC manual is as follows:

"Maximum water depth: 120 m

CAUTION
• Surpassing the maximum water depth may cause malfunctioning or permanent damage of the device.
• The ZH-L16 calculation model is valid only up to a depth of 120 m."


However what is surprising to me (and perhaps to Solodiver) is that the behaviour of the device at 130m is not documented. Certainly I was unaware of the behaviour prior to purchase. It emerged, if I recall correctly, from forum posts.

Its been a while since I checked the code so perhaps something has changed but the impression I am under is that the device will power off at 130m. Prior to this the depth will be displayed in a warning colour at 120m (CF43). I presume the device will re-activate when it goes shallower than 120m but will it be counted as a new dive? with the time and deco information reset? I'll have to check the code or perhaps you could summarise and confirm.


Perhaps it might be a good idea to document this behaviour in the manual. It is helpful to understand that HW will not change the behaviour at 130m and now the picture is getting clearer as a result.

Now as I mention I accept the situation and if I'm unhappy about it I have the option of changing the software myself. The only issue is the "surprise". Indeed in this regard the behaviour of the OSTC differs from pretty much every other computer I am aware of i.e. APD Vision, VR3, VRX, Shearwater Predator/Pursuit, Liquivision X1 which to the best of my knowledge will warn, display messages such as "Use Tables" or revert to time/depth info only but definitely not power off so I do think it is only fair to describe this behaviour in the users guide if that is your final decision.

Also I'm curious about your statement in the manual "The ZH-L16 calculation model is valid only up to a depth of 120 m" but in the DR5 manual you state:

"Decompression calculation is based on the Bühlmann ZH?L16 model, which is only valid up to 130 m. When reaching depths larger than 220 m, decompression calculation is turned off until reaching the surface."

and

"Maximum allowed operating depth 350 m ... 500 m (depending on the model) ZH-L16 model suitable for 220m"

So I think the OSTC description is inconsistent - you are enforcing this limit based on hardware limitations and not the deco algorithm and that should be emphasised in the documentation in my opinion.

By the way did you ever consider producing a 30bar version of the OSTC with a MS5541-30C. It seems to be completely compatible with the MS5541C although the resolution is 3mbar compared to 1.2mbar (although for me that is not such a big deal)? The price of the component is not that much greater either.

Anyway this is just my feedback. I'm not complaining or demanding anything.

Keep up the good work.

Regards, Stephen

[Solodiver]

Stephen, seems you are not aware that the unit will switch off at 130m, meaning it is bricked until you surface, connect to USB and find a magnet. No way to even get time or depth information. With these information any experienced diver should be able to surface alive (and find his way to the chamber if needed), without there is quite a high risk he is going to die.
And BTW: you forgot to mention the Suunto Gekko which is just able to display a depth in 2 digits meaning below 100m it just shows "--", but at least it is shwoing time information and after ascenting above -100m it is returning to "normal" readings.

And for the leagel discussion: I'm not the one who brought this up, but from my point of view, this would be a very serios and valid point for such a topic!

I'm just a little bit disappointed by the OSTC in general. Have been for some time, but this topic is not helping me to come over this feelings. When I purchased the unit I also have not been aware of this 130m limit. But much more important and the main reason for buying has been the two letters OS in the name. For me, this implied an active community. What I found is not was one or at least I expected from knowing other open source projects. Some key issues are that there a just very few developers who also are not communicate as public as one might expect, a Wiki which has not been writable and is even deleted in the meantime and the strong feeling of avoiding any modern social media based communication. I guess it is not good if open source projects stick to just a few key players, but on the other side there seems not to be much developers around interested in this topic which is essential for a project based where software is a key part. I guess it is valid to state, that I was trying to support the community around the OSTC with my abilities and I'm also responsible for the presence of many OSTC units in my regional diving community.

I'll not quit with the OSTC by now but delay this decision for some weeks where I'll not diving at all.

In the meantime I might try to hack my own firmware, but got stuck on compile issues right now. If there would be others interested in developing and enhancing the existing firmware I would be willing to spend many more nights with this project, but as of now I do not see much future in going this way. I'd then rather stick to closed source units where I just get what I buy for without the risk to get disappointed by being to passionate with it.

Bye,
Jan

[Anonymous User]

Solodiver Wrote:
> in the name. For me, this implied an active
> community.

...which fulfills your wish list (For free, of course)?

-> http://en.wikipedia.org/wiki/Open_source

> I'll not quit with the OSTC by now but delay this
> decision for some weeks where I'll not diving at
> all.

More time for your "contribution" to this project

Jo.

P.s.: I really wonder when someone complianing here actually looks into the code for the lock-out. You would be surprised.