Balluff BIS M-370-000-A02, Manual, Page: 114 / 198

STANDARD TCP/IP INTERFACE
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7
7.3 STANDARD TCP/IP - COMMAND & RESPONSE EXAMPLES
In standard TCP/IP, RFID commands issued by the host resemble Modbus TCP commands.
The BIS M-626 handles all handshaking tasks.
Moreover, the command & response packets need an additional word at the beginning of the
string:
Protocol Header 0xFF in MSB, < Node ID> in LSB.
Please notice that these two bytes are not considered part of the CBx command packet and
should not be counted in the Overall Length.
Below is the structure of the additional word required, named as
Word # 00 :
Word # Command Packet Element MSB LSB
00
Protocol Header in MSB: 0xFF
Node ID in LSB
0xFF <Node ID>
And similarly for the response:
Word # Response PACKET ELEMENT MSB LSB
00
Protocol Header in MSB: 0xFF
Node ID Echo in LSB
0xFF <Node ID Echo>
NOTE
These first two bytes will not be returned in the response packet for
commands executed by Node 01.
Therefore, the command packet structure for Standard TCP/IP applications is:
Figure 57 - Standard TCP/IP Protocol Command Packet Structure