LI-COR LI7200RS, Instruction Manual

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Appendix D. Configuration Grammar
Examples:
A typical (Data..) output record, with all items present, is shown below:
(Data (Ndx 215713)(CO2Raw 1.2831902e-1)(CO2D 2.2083146e1)(H2ORaw
5.5372476e-2)(H2OD 3.5485935e2)(Temp 2.5886261e1)(Pres 9.8157062e1)(Aux 0)
(Cooler 1.0537354))
A typical (Diagnostics..) record is shown below:
(Diagnostics (Sync TRUE)(PLL TRUE)(DetOK TRUE)(Chopper TRUE)(Path 63))
Data Polling (Software and Hardware)
A software command using the ENQ character (0x05) is available to query the
instrument for a data record over RS-232. When transmitted to the instrument, via
RS-232, the record is built as presently defined (Labels TRUE or FALSE, etc.), and is
added to the serial output queue. This software command is normally used when
the update frequency is set to zero, as shown in the command below.
(Outputs (RS232 (Freq 0)(DiagRec FALSE)))lf
The instrument also supports toggling of the Clear To Send (CTS) line to request a
data record. This hardware polling would be normally used when the update fre-
quency is set to 0 as described above. Since the CTS line is an input, the host soft-
ware should toggle the Request To Send (RTS) line from the host computer. This
method of transmitting a data record occurs when the CTS line goes from low to
high.
Users familiar with programming RS-232 interfaces may already understand that
RS-232 logic TRUE (1) is considered a low (or negative) voltage and logic FALSE
(0) is considered a high (or positive) voltage. Thus, the CTS toggle sequence would
look like:
+V (logic 0)
-V (logic 1)
0V
~50 µsec
D-12 LI-7200RS Enclosed CO₂/H₂O Analyzer