Cochran commander+ Owner's Manual page 41

Select Altitude <600 metres as One Zone (Off or On): This option provides "actual"
altitude for any given day at any diving location as explained in the previous section
"ALTITUDE ACCLIMATIZATION". With changes in barometric pressure due to
temperature and weather systems, it is possible, even expected, to have a different
apparent altitude at the same dive site from day to day.
While the seamless means of monitoring provides the most accurate decompression
schedule, all altitudes less than 600 metres above sea level can be treated in the
algorithm as sea level if so selected.
With this option OFF, the unit is calculating altitude in a seamless fashion. With this
option ON altitudes less than 600 metres above sea level will be treated as sea level.
Regardless of the selection, altitudes greater than 600 metres above sea level will be
treated in a seamless manner. From the factory, this is set to sense seamless altitude
from sea level to 4.5 km above sea level.
Select Decompression Time Display (Total, Stop, Both): There are three options for
the manner in which the decompression time is displayed. If you select TOTAL, the
decompression time displayed will indicate the total time you will spend in
decompression, including ascent to the surface.
Watch the Ceiling depth change in order to identify when to ascend to the next stop
depth. If you select STOP, the decompression time displayed will indicate the time you
must remain at the current Ceiling. When this time is 0:00, the Ceiling depth will
decrease and the new stop time will be displayed. If you select BOTH, the TOTAL time
and STOP time will alternate at the rate of once every 2 seconds. From the factory, the
unit is set to BOTH.
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