User's Manual

Table Of Contents
ABxF 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 LRP 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 up to
255 (FFH), where 0 means the tag can be re-read anytime. When Continu-
ous Read All mode is interrupted with other commands, the tag delay count
is stopped during execution of the other commands and then resumed.
The LRP830 will respond with an acknowledge packet followed by data
packets for each tag read.
CONFIG LED blinks after each packet transmission.
Field Content
Header <STX><STX>
Command Size Command length in bytes excluding the header, command size, checksum and
terminator bytes.
Command 8DH
Family ID Tag Family ID - 00H = all tags
Anticollision Index Anticollision not considered for this command, 00H
Start Address Tag address for the start of the read
Read Length 1-48 = start, 0 = stop
Tag Delay Number of tags that must be read before the same tag will be read again (0-255)
Checksum Optional Checksum
Message Terminator <ETX>
NOTE:
This command can not be used over a DeviceNet interface.
Copyright © 2000 Escort Memory Systems
124 LRP830-Series Long-Range Passive Reader/Writer