12
Preset Storing Commands
The ‘E’ command stores the position of the camera. Its single parameter is the preset
number into which to store the position. As indicated earlier, it is important to ensure
that the camera has been disabled for at least ¼ second prior to sending the “E’
command. For example, to store the current position of the camera into preset number
23:
‘L 0 <CR>‘
Wait ¼ second.
‘E 23 <CR>‘
The ‘EX’ variant of the enter preset command allows host supplied data to be stored
into a preset. The first parameter of this command is the preset number into which to
store the data. This parameter is followed by the four position data corresponding to
pan, tilt, zoom and focus to be stored into the preset. These data are all in the range of
0 to 4095. They are actually 12 bit two’s complement values. Consequently, the range
is -2048 to 2047, which when viewed as unsigned numbers would progress from 2048
to 4095, then 0 up to 2047. All position data for the SRD is in this format. In most
installations, the 0 position is approximately the center position of the full range of
motion of a given function. Positive values (0 to 2047) are toward the left for pan and
up for tilt. Lenses vary as to which direction is which so data for the lens type used in
the particular installation must be consulted if the application requires knowledge of the
directions. Here’s an example of this command:
‘EX 5 123 456 789 10 <CR>‘
Stores a pan position of 123, tilt position of 456, zoom position of 789
and focus position of 10 into preset number 5.
