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MPC561/MPC563 Reference Manual
MOTOROLA
Data Trace
Initial data trace message upon exit of background debug mode. Upon exiting BDM,
the next data trace message will be a synchronization message.
When data trace is enabled, the first data trace message will be a synchronization
message.
After 255 data trace messages have been queued without synchronization, the next
data trace message will be a synchronization message.
Upon assertion of an event In (EVTI) signal. If the READI module is not disabled
at reset, when EVTI asserts, if the EC field is 0b00 in the DC register, the next data
trace message will be a synchronization message.
Upon occurrence of a watchpoint, the next data trace message will be a
synchronization message.
Occurrence of queue overrun. A data trace overrun error occurs when a trace
message cannot be queued due to the queue being full (provided data trace is
enabled). 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
indicates that program/data/ownership trace overrun has occurred. The next data
trace message will be a synchronization message.
Data trace synchronization messages provide the full address (without leading zeros) and
ensure that development tools fully synchronize with data trace regularly. Synchronization
messages provide a reference address for subsequent DTMs, in which only the unique
portion of the data trace address is transmitted.
Data trace synchronization messages are of two types:
Data write
Data read
24.9.2.4 Data Write Synchronization Message
The data write synchronization message has the following format:
Figure 24-46. Data Write Synchronization Message Format
TCODE (13)
Data Value
[1 to 25 bits]
Max Length = 64 bits
[8, 16, or 32 bits]
Messages Cancelled
[1 bit]
[6 bits]
Min Length = 16 bits
Full target address