Honeywell N568X, Руководство по интеграции

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Power Control
Illumination/Aimer Control
The image engine illumination and aimer are controlled directly by the device. Management of these features, other than
enabling or disabling them, is not exposed to the end user.
Thermal Considerations
Care must be taken when designing the image engines into high ambient temperature applications where high duty cycle
or auto-trigger scanning is required. Such conditions can induce self heating of the image engine that can increase image
noise. This can result in degraded bar code reading performance and a reduction in image quality. The following precau-
tions should be taken when integrating the image engine.
• Turn off the aiming and illumination LEDs whenever possible.
• Applications where the illumination is not needed use the menu command SCNLED0. application where the aimer is not
needed use the menu command SCNAIM0.
• When auto-trigger operation is required, use presentation mode since this mode has “built-in” thermal management
features.
• Set the SDRTIM menu command to allow the processor to enter its power saving mode quickly after a bar code decode.
(See the SDRTIM description below.)
• Provide air flow to the image engine, when possible.
• Allow ambient light to assist the image engine in bar code decoding, thereby reducing the on-time of the illumination
LEDs.
Honeywell engineers have successfully designed the image engine into many applications as described above. Please
contact your Honeywell sales manager or solutions architect for detailed design assistance.
SDRTIMxxx Menu Settings
The menu setting SDRTIMxxx can be used to improve the trigger to decode time of the N56XX image engine in certain use
cases. However, in other use cases, the performance of the imager can be degraded substantially if this parameter is incorrectly
set. This section defines the SDRTIMxxx setting and discusses when it should be changed from its default configuration.
Definition of SDRTIMxxx
SDRTIM is an abbreviation for "Scan Driver Timeout". The setting is used to configure the length of time that the imager is
allowed to keep running after it is untriggered (either by a removal of the trigger signal, or by the successful decoding of a
bar code). The parameter xxx is the time, in milliseconds, that the imager continues to run. For example, if the parameter
SDRTIM200 is sent to the image engine, the imager continues to gather images with the illumination LEDs off, and the
decoder board will continue to store those images into memory for 200 ms after the imager is untriggered. When the
SDRTIM setting expires, the image engine transitions to standby mode to conserve power until it is triggered once again.
Negative Ramifications of Long SDRTIM Settings
Caution must be used when setting SDRTIM to a very long time period. Since the image engine never enters the power
saving standby mode, significant internal heating of the image engine can occur. In high ambient temperature situations,
this can result in elevated N56XX internal temperatures that can cause signal to noise degradation of the images. Conse-
quently, the images from the image engine can be unacceptable for human viewing, and bar code reading may no longer
be possible. Additionally, since the imager never enters standby mode, the battery life of battery operated systems will be
reduced.
Recommendations
It is not advisable to change the SDRTIM command from its default configuration, which is 1 ms (SDRTIM1). Please do not
change this setting from its default conditions without consulting a Honeywell Solutions Architect.
Warning! When selecting any continuous trigger mode, the ambient temperature should not exceed the
maximum operating temperature of the device. If the temperature exceeds the maximum operating
temperature, the performance of the device may be reduced, the life of the product may be shortened, and
permanent damage may occur to the device.
!