Vaisala FD12P - Manual (Page 70)

User's Guide _______________________________________________________________________
70 ______________________________________________________ M210296en-A
This format is also used when several devices are on the same line.
Use character 1 as the id if the id has not been set but a specific
message type is polled.
The FD12P does not echo the polling character string.
The answer message format is the following:
<SOH> FD <SP> id <STX> text <ETX><CR><LF>
The id field always contains two characters. If only one character has
been set as the id, the sensor will output an <SP> as the first character
in the field.
When there are several devices on the same line, the polled unit turns
the modem (DMX21) carrier on after it has acknowledged the request.
When the carrier is switched on, additional characters will appear
before the <SOH> (01 hex) character. The FD12P waits about 100 ms
after turning the carrier on before it starts to send the message. When
the FD12P has sent the message, it turns the carrier off. This will also
generate additional characters, which have to be ignored by the host.
FD12P Command Set
HELP Command
The operator receives information about available commands by
typing
HELP
↵
The HELP command sets are listed in Table 18 below.
Table 18 HELP Command Sets
Command Description
OPEN Assigns the line for operator commands
CLOSE Releases the line for automatic messages
MES Displays data message
AMES Number Interval Automatic message
(with parameters Number and Interval)
STA Displays status
PAR Parameter message
WPAR Weather parameter message
PRW Present weather message
CONF Password Updates configuration
CLEAN Sets clean references