LI-COR LI-7500, Инструкция по эксплуатации

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Appendix D
Appendix D D-3
because the
(BW...)
command is only recognized within the context of an
(Outputs...)
command.
The LI-7500 configuration grammar is case sensitive. That is,
(Outputs(BW 10))
will work,
while
(outputs(bw 10))
will not.
Who Sends What
Not all of the commands in the LI-7500’s grammar are really commands. Some are designed
to be used by the LI-7500 to package outgoing data. The
(Data..)
command, or record,
might look like this
(Data (CO2D 2.2083146e1)(H2OD 3.5485935e2)(Temp 2.5886261e1)(Pres
9.8157062e1))
This record is showing the latest values of CO
2
and H
2
O mole density (mmol m
- 3
),
temperature (°C), and pressure (kPa). The fields present in a
(Data..)
record, and how often
they are output, is determined by the
(Outputs..)
command.
Once it has established communications with a host computer (discussed in the next section),
the LI-7500’s RS-232 communications is largely made of up of outgoing
(Data..)
and
(Diagnostics..)
records. The only other type of records it might send are
(Error..)
and
(Ack..)
. The
(Error..)
record is sent whenever the LI-7500 receives a command it cannot