Chapter 4 _________________________________________________________________ Operation
VAISALA ________________________________________________________________________ 73
MESSAGE Command
The
MESSAGE
command is used for displaying messages. The
command format for the
MESSAGE
command is
MESSAGE
Message_number
If the message number is not specified, FS11 displays a default message.
The default message is the message that has been selected for automatic
or polled mode with command
SET MESSAGE TYPE
.
NOTE
When displaying a message with the
MESSAGE
command, the
message frames are not displayed.
All message frames end with
−∗
which represent the carriage return and
line feed characters. This character is also used as a line separator in
multi-line messages.
The contents of the messages are described in the following sections.
MESSAGE 1, FS11
Message 1 is a message of fixed length where both extinction coefficient
and background luminance values are shown. The message format is as
follows:
!
FSA
∀
EXT 0.85 AL 0 ALS 8746 AL 0
#
CSUM
∃−∗
where
!
=
Start of the heading (ASCII 1)
FS
=
FS11 sensor identifier
A
=
First character of the unit identifier, if the ID is not
defined it is replaced by a space character
∀
=
Start of the text (ASCII 2)
EXT 0.85
Extinction coefficient identifier and extinction
coefficient value, unit km
-1
, 1 min average
AL 0
Alarm status of the visibility sensor
ALS 8746
Background luminance identifier and BL value, unit
foot-lambert. A foot-lambert equals 1 /
π candela per
square foot, or 3.426 cd/m
2
AL 0
Alarm status of the background luminance sensor
#
End of the text (ASCII 3)
CSUM
Checksum CRC16
∃
End of the transmission (ASCII 4)
−∗
CR + LF (ASCII 13 + ASCII 10)
