Motorola MPC533 Reference Manual page 977

[6 bits]
TCODE (10)
Figure 22-22. Program Trace Correction Message Format
22.3.2.4 Synchronization Messages
A program trace synchronization message is transmitted via the auxiliary port (provided
program trace is enabled) for the following conditions:
• Initial program trace message upon exit of any system reset will be a
synchronization message.
• Upon exit of sleep, deep-sleep and low power down mode, the first BTM will be a
synchronization message.
• Initial program trace message upon exit of background debug mode. Upon exiting
BDM, the next BTM will be a synchronization message.
• When BTM is enabled, the first BTM will be a synchronization message.
• After 255 program trace messages have been queued without synchronization, the
next BTM will be a synchronization message.
• Upon assertion of an event In (EVTI) signal. If the READI module is not disabled,
an EVTI assertion will cause the next BTM to be a synchronization message
(provided the EC field is 0b00 in the DC register).
• Upon occurrence of a watchpoint, the next BTM will be a synchronization message
(provided program trace is enabled).
• Occurrence of queue overrun. A program trace overrun error occurs when a trace
message cannot be queued due to the queue being full. This causes the message
queue to be flushed, and an error message is placed as the first message in the queue.
The error code within the error message will indicate that program/data/ownership
trace overrun has occurred. The next BTM will be a synchronization message.
• Sequential instruction count overflow. When the sequential instruction counter
reaches its maximum count (up to 256 sequential instructions may be executed), the
next BTM will be a program trace synchronization message.The sequential
instruction counter is reset.
• Upon entering or exiting code compression mode, the next BTM will be a
synchronization message.
• The next change-of-flow instruction fetch following VSYNC will be a
synchronization message.
MOTOROLA
PRELIMINARY—SUBJECT TO CHANGE WITHOUT NOTICE
[1 - 8 bits]
Number of instructions to rewind from trace
Max Length = 14 bits
Min Length = 7 bits
Chapter 22. READI Module
Program Trace
22-45