LI-COR LI-7500, Instruction Manual

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Appendix D
D-16 Appendix D
Examples:
1. 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))
2. 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 LI-7500 for a
data record. When transmitted to the LI-7500, the record is built as presently defined (Labels
TRUE or FALSE, etc.), and is added to the 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 LI-7500 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 frequency is set to 0 as
described above. Since the CTS line is an input, the host software 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. The CTS line must be in the active (high) state for