Vaisala WS425 - Manual (Page 56)

USER'S GUIDE____________________________________________________________________
56 __________________________________________________________________ M210361EN-E
Send Identification Command (aI!)
This command is used to query sensors for their SDI-12 compatibility
level, model number, and firmware version number.
The following is an example of the command:
aI!
where
a = The sensor address.
I = The send identification command
! = Terminates the command.
The following is an example of the response:
allccccccccmmmmmmvvvxxx . . . xxx<CR><LF>
where
a = The sensor address.
ll = The SDI-12 version number, indicating
SDI-12 version compatibility; for example,
version 1.1 is encoded as 11.
cccccccc = An 8-character vendor identification Vaisala_
mmmmmm = 6 characters specifying the sensor model number
WS425.
vvv = 3 characters specifying the firmware version
604.
For example,
xxx ... xx = An optional field, up to 13 characters, used for a
serial number or other specific sensor
information that is not relevant for operation of
the data recorder (not used).
<CR><LF> = Terminates the response.
Address Query Command (?!)
When a question mark (?) is used as the address character with the
acknowledge active command (a!), the sensor will respond as if it is
being addressed on the SDI-12 bus. For example, if a sensor detects ?!, it
will respond with a<CR><LF>
, no matter what its address may be. This
will allow a user to determine the address of a sensor. The user should
understand that if more than one sensor is connected to the bus, they will
all respond, causing a bus contention.