User Manual

CHAPTER 6: COMMAND PROTOCOLS
COBALT HF RFID CONTROLLERS OPERATOR’S MANUAL
P/N: 17-1320 REV 01 (03-06) PAGE 66 OF 116
6.3 CBX C OMMAND P ROTOCOL
The CBx Command Protocol, utilized by the Cobalt -485 and -IND models, includes
Multi-drop Subnet16 networking support for use with Industrial Ethernet applications.
CBx is based on a double-byte oriented packet structure where commands always
contain a minimum of six data “words,” even when one (or more) parameters are not
applicable to the command. CBx does not support the inclusion of a checksum byte.
The CBx packet structures described herein are protocol independent and can be
implemented the same for all Industrial Ethernet protocols (Ethernet/IP, Modbus TCP,
etc.).
6.3.1 CBx – Command Procedure
C OBALT HF-CNTL-485-01 – COMMAND P ROCEDURE
Commands are initiated by a host PC or Programmable Logic Controller (PLC) and are
distributed to the controller via a Subnet16 Gateway or Subnet16 Hub Interface Device
that is connected to the host or PLC by standard Ethernet cabling.
After a command is sent, it is executed either directly by the interface device (Gateway or
Hub) or is otherwise routed to the RFID controller specified in the command. Note that
when issuing controller-bound commands, instructions are directed to the appropriate
RFID controller by specifying the “Node ID Number” of the particular controller. Each
Cobalt -485 Controller on a Multi-drop Subnet16 network is assigned an individual Node
ID number.
C
OBALT HF-CNTL-IND-01 – COMMAND P ROCEDURE
Commands are initiated by a host PC or Programmable Logic Controller (PLC) and are
distributed directly to the controller via an M12 D-Code to Ethernet cable.
After a command is sent, it is immediately executed by the Cobalt Controller. Note that
instructions are directed to the controller by specifying in the command the “Node ID
Number” of the Cobalt Controller. For the Cobalt HF-CNTL-IND-01, the Node ID will
always be 01 (0x01).
6.3.2 CBx – Response Procedure
Following the execution of an RFID command, the controller will automatically generate a
host-bound response message that contains EITHER the results of the attempted
command or an error code if the operation could no be completed successfully.
Similar to ABx Fast, all CBx commands will generate a response from the controller.
Before the host can send another command to the controller, it must first process
(remove from memory) the controller’s pending response data.