User's Manual

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Merlin II Protocol Analyzer User’s ManualCATC SW Version 2.30
10.5 Viewing Packets in LMP and L2CAP Messages
LMP and L2CAP Messages can be "opened" to reveal
their constituent packets by double-clicking the first
cell in of the message or clicking once on the small
arrow on that same cell. The packets will then display below the message.
The following screenshot shows an example of a message and its packets.
10.6 Types of LMP and L2CAP Messages
If you scroll through a trace, you will see three kinds of message:
• LMP Signalling Message
• L2CAP signalling Message
• L2CAP Data Transfer Message
Each message has the same basic message header but differs in its payload.
LMP and L2CAP Signalling messages have payloads of commands for
establishing LMP and L2CAP channels. L2CAP Data-Transfer messages
have a payload that may include RFCOMM, SDP, or TCS data. In order to
Message
Packets
making up
the
message
LMP Signalling Message
L2CAP Signalling Message
L2CAP Data Transfer Message
Payload
Payload
Header
Payload
Header
Header