User's Manual

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ABxS Command 8D (8DH): Continuous Read All
DESCRIPTION
Starts and stops Continuous Read All mode for multiple tags.
DISCUSSION
Continuous Read All mode is set by the length byte. To start Continuous
Read All mode send the command with valid, non-zero value for the length
of the read (1-48). Stop the mode by sending the command with a read
length of 0.
While in this mode, any other command can be issued and it will be handled
properly. After processing the new command, the LRP820 will resume the
Continuous Read All mode.
The command has a parameter, tag delay, that can prevent multiple reads of
the same tag. A tag is not read a second time until a specified number of
tags have been read since it was last read. Allowed value are from 0 to 255
(FFH), where 0 means the tag can be re-read anytime. When Continuous
Read All mode is interrupted with other commands, the tag delay count is
stopped during execution of the other commands and then resumed.
The LRP820 will respond with an acknowledge packet followed by data
packets for each tag read.
CONFIG LED blinks after each packet transmission.
Field Remarks
Command Command number in hex preceded by AAH
Family ID Tag Family ID - 00H = all tags
Anticollision Index Number of tags expected
Start Address Tag address for the start of the read
Read Length 1-48 = start, 0 = stop
Tag Delay Number of tag that must be read before the same tag will be read again
(0-255)
Message Terminator FFFFH
NOTE:
This command can not be used over a MUX32 interface.
Copyright © 2000 Escort Memory Systems
LRP820-Series Long-Range Passive Reader/Writer
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