EMS LRP2000 Series, Руководство оператора

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RFID Interface
LRP2000 Long Range Passice Reader/Writer
57
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ABxS Command 0DH: Stop/Start Continuous Block
Read
DESCRIPTION
When in Continuous Block Read mode, the controller sends block
read commands continuously to any tag in range of the antenna.
When a tag comes within range, it is read and the data passed to the
host computer. The controller continues to read the tag but will not
send the same data to the host until the tag has been outside the RF
field for a specified time period. This Delay Between Identical
Decodes parameter prevents redundant data transmissions when the
controller is in Continuous Block Read mode.
DISCUSSION
The Start/Stop Continuous Block Read command contains three
parameters: read length, start address, and delay between identica
decodes. The read length parameter switches the mode. Any valid,
non-zero length (1-48) will set the controller into Continuous Block
Read mode. A read length value of 00H will turn Continuous Block
Mode off. The Delay Between Identical Decodes parameters can have
a value of 0 to 60 seconds. When the Delay Between Identical
Decodes is set to 0, the controller will continuously read AND transmit
tag data to the host. This can flood the buffers and cause
communication errors and data loss. If the controller receives other
commands from the host, it will execute them and then resume
Continuous Block Read mode. To exit Continuous Block Read mode,
issue the command with a read length of 0.
In Continuous Block Read mode, the LEDs will display as follows:
LED Behavior Description
ANT ON Assumes the Antenna
is powered and
functioning
CONFIG BLINK Tag entered the RF
field
RF ON A tag has been read
and is still in the field
RF OFF A read tag has been
out of range for the
specified time