Session Programming - ashtech DG16 Reference Manual

With the Session Programming feature, you can pre-set up to 10 observation
sessions in the receiver. You can program the receiver to wake-up at a specified
time and preform specified tasks such as output position and velocity data. In
addition, you can set a session time offset that shifts the session start and end
times by a predetermined amount every day.
Session programming can also be used to put the receiver into sleep mode.
When the receiver is in sleep mode, most of the receiver functions are suspended
which conserves power. Using preset session start times, the DG16 automatically
wakes up in time to perform specified tasks for the next session and returns to
sleep when the session is complete.
Session programming is enabled by the $PASHS,SES command. You must
enable the individual sessions and set session parameters such as the start/stop
times, recording interval, elevation mask, minimum number of satellites, and the
data type for each session.
In addition, you need to set the mode (session in use switch), the session
reference day, and the desired session offset. The mode is either Yes, No, or
Sleep. If the mode is set to No, then session programming is disabled, even id an
individual session is set. If the mode is set to Yes, then session programming is
enabled, and any enabled individual sessions are activated. if the mode is set to
Sleep, then the receiver goes into sleep mode, once an activated session has
completed. and the DG16 wakes just prior to the next session.
The session reference day is a mandatory parameter that determines both the
start day of session programming data collection and is used in conjunction with
the Offset to determine the session start and end times. The reference day must
be set equal to or earlier than the current day, or else the sessions will not run. If
the reference day is later than the current day, then the session start and end
times decrement by the offset multiplied by the numbers of days between the
current day and the reference day. For example, suppose you wish to collect data
everyday for seven days observing the identical satellite window on each day.
Since the GPS window moves backwards four minutes per day, set the offset to
0400 and set the reference day equal to the current day. For each subsequent
day of data collection, all sessions will start and end four minutes earlier than the
previous day. By the seventh day the sessions will start and end 28 minutes
earlier than on day 1.
32 DG14 and DG16 Board & Sensor Reference Manual