Honeywell N568X, Руководство по интеграции

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Lower power trigger mode causes the N56XX to power off between scans. A manual trigger activation causes the power to
be turned on. The trigger line is controlled on the N56XX with a pullup so the line must be left floating to successfully enter
the low power modes. The Aim/nWake line must be idle high at the time of power down, otherwise the unit will not go into
stop mode. The scanner scans until a timeout or a decode, indicating the appropriate status (beeper and good read LED),
outputs the data, and, if the trigger has been released, turns off the power. See
Thermal Considerations on page 2-1.
Presentation Mode
Presentation Mode uses ambient light to detect bar codes. The LEDs are dimmed for ambient conditions until a change
occurs in the imager’s field of view. Then the LEDs become brighter automatically to read the code. If the light level in the
room is not high enough, Presentation Mode may not work properly. See
Thermal Considerations on page 2-1.
Streaming Presentation Mode
When in Streaming Presentation mode, the scan illumination remains on all the time to continuously search for bar codes.
Three modes are available; Normal, Enhanced, and Cell Phone. Normal mode offers good scan speed and the longest
working ranges (depth of field). Enhanced mode gives you the highest possible scan speed but slightly less range than Nor-
mal mode. Enhanced mode is best used when you require a very fast scan speed and don’t require a long working range.
Cell Phone mode optimizes the engine to read bar codes from mobile phone or other LCD displays. When this mode is
enabled, however, the speed at which printed bar codes may be scanned might be slightly slower. See
Thermal
Considerations on page 2-1.
Status Indicators
Good Read LED (Pin 10)
The N56XX provides a pin on the host interface connector (nGRLED) that can be used to drive an LED to indicate a Good
Read status. This signal is driven by an Open Drain NC7WZ07 device with a V
Omax
= 5.5V through the 100K pull up resis-
tor on the engine. It is capable of sinking 32 mA at Vin = 4.5V (N56XX supply voltage) or 24mA at Vin = 3.3V.
Beeper (Pin 9)
The N56XX provides a pin on the host interface connector (nBEEPER) that provides a PWM output for generating audible
feedback to the user. This signal is used to indicate the status of the device using a variety of patterns and frequencies.
This signal is driven by an Open Drain NC7WZ07 device with a V
Omax
= 5.5V through the 100K pull up resistor on the
engine. It is capable of sinking 32 mA at Vin = 4.5V (N56XX supply voltage) or 24mA at Vin = 3.3V.
Power Down/nFlash Out (Pin 8)
The N56XX provides a pin on the host interface connector (PWRDWN/nFLASH_OUT) that provides an indication when the
device is powered down (active high) or allow external illumination to be synced with the sensor’s exposure (active low),
respectively.
When configured for PWRDWN (GPIOFO0), the signal is designed to be used as an indication to the host that the engine is
currently powered down. The ability to power down the unit is limited to RS232 Low Power Mode (TERMID0;TRGMOD2).
When configured (enabled using GPIOFO1), the nFLASH_OUT signal is designed to be used as an indication to the host to
turn on (not drive) an external illumination source. It reflects the state of the sensor's exposure.
Note: If GPIOFO1, nFLASH_OUT will operate with or without engine illumination (SCNLED). However, if FLACON is also
used (value > 0), Engine Illumination will not be enabled.
To optimize the performance of the external illumination, verification of the time it takes to enable the external illumination in
response to the nFLASH_OUT control signal is recommended. Based on the results, FLACON can be configured to ensure
that illumination will be ON just before integration (exposure). This will ensure that illumination is not turned ON too prema-
turely, resulting in inefficient use of power, or too late, resulting in inadequate illumination during integration time. The FLA-
CON value ranges from 0 to 127, where Start-up Time = FLACON * 16.7 µs. Please note, that this Start-up Time can be set
in increments, which are not linear for steps less than 10. For example: 5 steps ~ 75 µs delay, 4 steps ~ 49 µs delay, 3 steps
~ 36 µs, and 2 steps ~ 24 µs delay. Setting FLACON to 0 or 1 is the equivalent of having no Start-up Time.
An example of this follows: