Log for Tusa Zen DC

[Jef Driesen]

On 12-09-14 08:55, Willem Ferguson wrote:
> I really struggle with this dive computer. It is a Zen IQ900 DC of a
> colleague who is heavily involved in NAUI Scuba Diver training (i.e.
> "open water"). So most of his dives are in the 3m to 15m range. He wants
> to see more detail of gas loading because of the yo-yo diving inherent
> in introductory training. Subsurface does an upload of data, but the
> data are weird.
>
> Firstly, The DC should have 99 dives, the maximum number stored by the
> Zen. On Subsurface it only shows 10 dives.

Linus' explanation is correct. The number of logbook entries (with just a 
summary of the dives) is much larger the available memory for storing the 
profiles. If you want to store more profiles, you need to increase the sample 
interval (for example 30 seconds instead of 10s).

> Secondly Subsurface sees some very funny values being read, as is
> obvious from the xml dive log. For instance, on the last dive, it sees
> cylinder pressures as well as a gas mixture that should not come from
> the DC as it is a) not air-integrated and b) nitrox was disabled for
> that dive. The temperature values are crazy. The depth profiles profile
> look about right.

This is most likely a bug in the libdivecomputer parser. Unfortunately these 
kinds of parser bugs happen all the time for oceanic devices, because they use a 
slightly different data format for each device. To fix this, we just need to 
find the difference and add yet another device specific change in the atom2 parser.

> Thirdly the depth scaling that Subsurface does for the dives is crazy
> for all except the first and last dives.

I'll leave this question for someone else...

Jef