Help needed decoding data

[John Van Ostrand]

Good news everyone!

I've finally figured it out, at least close enough that I can claim victory.

It's interesting how an idea has inertia. I had originally thought I had
isolated the depth bits because they were the most dynamic bits. I was
stuck thinking those were depth until I realized they could have been depth
change values. I'm happy to say I wasn't far off, they were ascent rate
values in feet, sampled every two seconds with intermediate samples
interpolated.

The bits I that turned out to be depth change were so few that I had not
even considered them for depth and I never reconsidered them when I started
working on depth change, until today.

The depth change samples are 7 bits of depth change in 0.25 foot increments
allowing a max change of 15.75 ft/second. My depth changes have all been
less than 1.5 f/s so I haven't had a depth change that uses those higher
bits, which are always 0.

What I'm still missing is the starting position. All depth change samples
I've looked at over several dives have fit *exactly* what the vendor
software reports however I haven't found the starting  depth. It's over 6'
because of how the computer works.

The temperature is odd but I have it accurate. It's in degrees F from 20F.

The only thing missing is that i have 32 bytes in a grouping of 24 samples
that are unallocated to any sample. I can probably ignore them.


-- 
John Van Ostrand
At large on sabbatical
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