Datalogic GWY-01-PBS-01, Reference Manual

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GWY-01-PBS-01
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4 COMMAND PROTOCOL
A command is initiated by a host PC or
Programmable Logic Controller (PLC) and is
distributed to the Gateway over a network connection. Once issued, the command is then
executed directly by the Gateway or is otherwise routed to the appropriate RFID controller
(specified by its numerical “
Node ID ” value, for which there are 16).
In general, there are two types of commands that can be issued:

Controller Commands - commands intended for one of the attached RFID
controllers. “ Read Data ” and “ Write Data ” are two common controller commands.

Gateway Commands - commands intended for the Gateway itself. Gateway
commands are those commands that query the Gateway for information or instruct
the Gateway to perform a task. The commands “
Get Node Status List ” and “ Set
Notification Mask ” are examples of Gateway commands.
4.1 CBX COMMAND PROTOCOL OVERVIEW
In order to execute RFID commands properly, the RFID device and host computer must be
able to communicate using the same language. The language that is used to communicate is
referred to as the
Command Protocol . The command protocol used by GWY-01-PBS-01 is
called " CBx ".
The
CBx Command Protocol is an advanced protocol that supports Multidrop Subnet16
networking with TCP/IP, Profibus and Industrial Ethernet applications. It is based on a
double-byte oriented packet structure where commands always contain a minimum of six
data “words” (12 bytes) - even when one or more packet elements are not applicable to the
command.
The CBx packet structures described herein are protocol independent and therefore can be
implemented the same for all protocols (Ethernet/IP, Modbus TCP, Profibus, etc.).
NOTE
For complete command and response packet structures and examples of
each RFID command, refer to the
CBx Command Protocol Reference
Manual available at: www.automation.datalogic.com.