Campbell Scientific SC-IRDA CSL CS I/O to Infrared Interface - Manual (Page 9)

SC-IRDA Infra-red Communications Interface
5
4. Operating Instructions
Whichever computer system or software package is used (see
below) in all cases the IRDA port on the computer needs to be
aligned with the sensor on the SC-IRDA for at least 5 to 10
seconds before attempting to communicate with the datalogger.
This is to allow time for the two IRDA devices to recognize each
other and to negotiate a working IR link. If a link is not
established before you attempt communication, that specific
attempt may fail or may take a prolonged period of time.
4.1 Palm OS Handheld Software
To utilize the IRDA connection you need to select the IRDA option in the
screens where the station parameters are selected. The program will then
operate as normal from that point.
The only points to note that are specific to the IRDA interface are that you
must ensure the IRDA sensors on the Palm PC and SC-IRDA are properly
aligned. Check your Palm PC carefully, as the sensors are not easily identified
on some models.
Once you have established a connection to the datalogger you will need to keep
the Palm PC in the correct orientation to maintain the connection. The
PConnect software will tolerate a short disturbance to the connection and the
various protocols will ensure no loss of data. However, if the connection is
broken for more than a few seconds the SC-IRDA may shut down. This may
then require PConnect to be terminated, restarted, and the connection re-
initialized before further data can be collected or displayed.
Some of the older, slower, Palm PCs are not able to keep up with
the speed of transfer of data when using the option to read a
datalogger program from the datalogger back to the Palm. For
long programs you may find sections of the program missing,
and so you should not rely on this mode. This should not
generally be an issue, as the master copy of the program is
normally generated and retained on the PC.
4.2 PC Software
The SC-IRDA will work reliably with many PC communications packages.
However, all IRDA interfaces have one characteristic that can upset automatic
programs that expect to communicate via a serial port; this is the time that the
interface takes to initialize. This can take several seconds as opposed to a few
milliseconds with a standard serial port.
Many of Campbell Scientific's own programs will generate a warning message
in a log file, or, in the worst case, not operate at all because of this unexpected
delay. The degree of the problem varies to a degree with the speed of the PC
being used, as faster PCs will have a shorter initialization time. Some guidance
on the use of Campbell Scientific programs with the SC-IRDA interface is
given below.
NOTE
NOTE