User's Manual
Table Of Contents
- Table of Contents
- 1. Overview
- 2. Quick Installation
- 3. Detailed Installation
- 4. Updates
- 5. Software Overview
- 6. Recording Wizard
- 7. Recording Options
- 8. Display Options
- 9. Reading a CATC Trace
- 10. Decoding Higher Protocols
- 10.1 Introduction
- 10.2 LMP and L2CAP Messages
- 10.3 Decoding and Viewing Higher Protocol Data
- 10.4 Tooltips
- 10.5 Viewing Packets in LMP and L2CAP Messages
- 10.6 Types of LMP and L2CAP Messages
- 10.7 Viewing L2CAP Channel Connections
- 10.8 Viewing Protocol Messages and Transactions
- 10.9 Changing Protocol Assignments
- 11. Other Features
- How to Contact CATC
- Warranty and License
- Index
129
BTTracer Protocol Analyzer User’s ManualCATC Version 1.0
Acknowledgments are easily seen in BTTracer traces because BTTracer
adds an Ack’d field on data packets of the transmitting device. This means
that you do not have to hunt through the trace to see if the packet was
acknowledged.
The following screenshot shows two examples of Acknowledgments.
Implicit NACK - Packet 14577 is a data packet sent by the piconet Master
device. Packet 14579 should have been a data packet with an
acknowledgment. Instead, it is an empty packet. This Master interprets this
empty packet as an Implicit NACK (i.e., implicitly not acknowledged).
BTTracer summarizes this packet exchange by adding an Ack’d fieldtothe
Master’s data packet and setting the Ack’d field to Imp Nak.
ACK - Packet 14580 is the Master’s retransmission of the data sent in
packet 14577. Packet 14582 is the reply by the Slave device. This reply
contains an ARQN field with a value of (= Acknowledge). BTTracer
summarizes this packet exchange by setting the Ack’d field on packet
14580 to Ack.