PRECITEC CHRocodile C, Руководство по эксплуатации

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2.14 STO Command
Short description:
The command STO stops serial data output
This mode can be stored in the nonvolatile memory, so on the next power up the CHRocodile C
will not begin to send measurement data until the output is restarted by the "STA" command.
Command syntax:
$STO
Command Description
$STO
Response: $STO [CR]ready[CR/LF].
Stops serial data output
2.15 THR Command
Short description:
The command THR lets you specify an intensity threshold for the distance detection.
It may be useful to specify a high threshold to reject all noise spikes during a measurement or to
specify a low threshold to get a (noisy) result from very black surfaces. When the signal is below
the threshold, 0 is output for distance and intensity. The threshold is in arbitrary units which may
be subject to change in future software versions.
At faster sample rates, lower settings for threshold can be used than at slower sampling rates.
The reason is, that at slower sampling rates, the stray light of fiber and coupler is integrated
longer on the detector. Even though this signal is automatically subtracted as "dark reference",
the statistical variations of this signal are stronger, the higher the dark signal becomes. If a
typical value for good noise suppression and maximum sensitivity at 2kHz sampling rate could
be 20, at 100Hz 50 would be needed.
If the sensor doesn’t detect a signal which passes the threshold, 0 is output for distance and
intensity.
Command syntax:
$THR <I>
Param: <I> is intensity threshold
Command Description
$THR 35
Response: $THR 35[CR]ready[CR/LF].
Write Intensity Threshold
$THR ?
Response: $THR ? 35ready[CR/LF].
Read Intensity Threshold