REFERENCES
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• For readers using the hardware trigger parameter, a reading cycle corresponds
to a trigger press (ON) + one of the following OFF events:
trigger release (for trigger active level)
a second trigger press (for trigger active pulse)
trigger-off timeout (see par. 4.5.2).
When one read per cycle is selected, the device decodes only one code during the
ON period and immediately turns the reader OFF. It is only possible to read another
code when the next ON time occurs.
In multiple reads per cycle, the ON period is extended so that the device can
continue decoding codes until an OFF event occurs. For software trigger mode, the
flash on period is immediately reset after each read and therefore extended. If
another code is decoded before the reset flash on period expires, it is again reset and
the effect is that the device remains ON, decoding codes until the flash on or timeout
period expires.
The Safety Time parameter should be used in this case to avoid unwanted multiple
reading of the same code, see par. 4.5.4.
4.5.4 Safety Time
Safety time prevents the device from immediately decoding the same code more than
once. Same code consecutive reading can be disabled requiring the reader to be
removed from the code (no decoding) for at least 400 ms, or a timeout can be set up
to 9.9 seconds before the decoder will accept the same code. Reading is immediate if
the code changes.
The safety time parameter is not applicable when reading stacked codes or when
setting one read per cycle in hardware trigger operating mode, since these settings
require voluntary action by the user.
4.6 DECODING PARAMETERS
CAUTION
These parameters are intended to enhance the decoding capability
of the reader for particular applications. Used incorrectly, they can
degrade the reading performance or increase the possibility of a
decoding error.
4.6.1 Ink-Spread
The ink-spread parameter allows the decoding of codes, which are not perfectly
printed because the page texture tends to absorb the ink.
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