User's Manual

Table Of Contents
6.4 ABx Fast Protocol
The difference from the standard ABx are:
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The command/response packet contains the packet size
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You can include a checksum in the command
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The headers and terminator are ASCII characters
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Since ABx Fast is a binary protocol, the Xon/Xoff handshake
cannot be used.
ABx Command Packet Structure:
The command protocol is based on the following minimal packet structure.
The data field and the checksum may not be present depending on the com
-
mand type and your checksum setting.
Field Number of Bytes Content
Header 2 <STX><STX> (02H, 02H)
Command Size 2 Packet length in bytes excluding the header, command
size, checksum and terminator bytes.
Command 1 Command Code
(Data) variable command data/parameters
(Checksum) 1 Optional Checksum
Terminator 1 <ETX> (03H)
Following a successful operation, the LRP820 will respond with the follow
-
ing. The data field and the checksum may not be present depending on your
checksum setting.
Field Number of Bytes Content
Header 2 <STX><STX> (02H, 02H)
Response Size 2 Packet length in bytes excluding the header, response
size, checksum and terminator bytes.
Command 1 Command Echo
(Data) variable response data
(Checksum) 1 Optional Checksum
Terminator 1 <ETX> (03H)
Copyright © 2000 Escort Memory Systems
LRP820-Series Long-Range Passive Reader/Writer
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6.5 ABx Fast Protocol