Vaisala FS11P - FD12 Emulation; FD12 Message 2

Chapter 4 _________________________________________________________________ Operation
VAISALA ________________________________________________________________________ 89
where
CSUM
=
Checksum CRC16
∃
=
End of the transmission
−∗
=
CR + LF
FD12 Emulation
For compatibility in the system level, the FS11P sensor also supports the
message format, frames, and polling format of Vaisala FD12 Visibility
meter and Vaisala FD12P Weather Sensor. The FD12/FD12P polling
format is accepted only when the FD12/FD12P message emulation is
selected. The FD12/FD12P polling format is as follows:
%
FD id message_number
−
The parameter message_number refers to the FD message number.
FD12 Message 2
The FD12 message 2 emulation mode is selected with the command SET
MESSAGE TYPE FD12MSG2.
The message format of the emulated Vaisala FD12 message number 2 is
presented below:
!
FD A
∀
00 1810 1353 //// // /////
#−∗
----------------------------------------
¦¦ ¦ ¦ ¦ ¦ ¦_____reserved for options
¦¦ ¦ ¦ ¦ ¦________reserved for options
¦¦ ¦ ¦ ¦_________reserved
¦¦ ¦ ¦_________visibility 10 min average in meters
¦¦ ¦________visibility 1 min average in meters (max. 75000m)
¦¦____hardware status 0 = OK
¦ 1 = alarm (data OFF, see STATUS message)
¦ 2 = warning (see STATUS message)
¦_______data status 0 = normal, FD12 alarm limits not supported
The total amount of characters in the message is 40. The transmission
times are: 1.3 s at 300 bps (10-bit char), 0.17 s at 2400 bps, 0.04 s at
9600 bps.