Lantronix LSB4, Reference Manual, Page: 37 / 74

LSB4 Reference Manual Filter Commands
6-7
Set/Define Filter (cont.)
Parameters pattern
Two bytes (four hexadecimal characters, or 16 bits) long and
defines the characters contained in each data packet. The
four hexadecimal characters must be preceded by 0x. Wild-
cards ( * ) may be used in this field. An example of a wild
card is shown below [Figure 6-7]:
Figure 6-7: Wild Card
offset
Up to three hexadecimal characters long and defines where
in the data packet the LSB4 is to look for the specified pat-
tern. The hexadecimal characters must be preceded by
0x .
offset may be a hexadecimal value from 000 to 5ff. 000 indi-
cates the first data position in the data packet. For example,
if you specify the hexadecimal value 10, the LSB4 will look
for the first character of the pattern at the seventeenth data
position in the data packet.
Protocol identifier
Identifies or selects one of the protocols present in the local
area network. A protocol can be identified by entering hexa-
decimal characters, or by selecting a protocol mnemonic
(for example, IP.)
Protocols may have mnemonics for subgroups and these
subgroups may have further subgroups. For clarity, proto-
cols one, two, or three are identified. In the syntax on page
6-9, the protocol mnemonics in the leftmost column are lev-
el one.
If a level one protocol is specified and has level two and
three protocols, the filter will act upon the level one proto-
col and all of the level two and three protocols as shown in
the syntax below. If a level 2 protocol is included, the filter
will act upon the combination of the specified level one pro-
tocol, the specified level two protocol and any of the level
two protocol's level three protocols. When a level three pro-
tocol is included, the filter will act upon only that combina-
tion of level one, two, and three protocols.
SET FILTER 1 APPEND PATTERN 0X12*4 0X23
Sport
and
Dport
are exceptions and
are not protocol
mnemonics; they
can be used (page
6-10) to specify a
protocol port.