MPC5553/MPC5554 Microcontroller Reference Manual, Rev. 5
25-48 Freescale Semiconductor
25.11.12.2.4 Resource Full Messages
The resource full message is used in conjunction with the branch history messages. The resource full
message is generated when the internal branch/predicate history buffer is full, or if the BTM Instruction
sequence counter (I-CNT) overflows. If synchronization is needed at the time this message is generated,
the synchronization is delayed until the next branch trace message that is not a resource full message.
The current value of the history buffer is transmitted as part of the resource full message. This information
can be concatenated by the tool with the branch/predicate history information from subsequent messages
to obtain the complete branch history for a message. The internal history value is reset by this message,
and the I-CNT value is reset as a result of a bit being added to the history buffer.
Figure 25-30. Resource Full Message Format
25.11.12.2.5 Debug Status Messages
Debug status messages report low power mode and debug status. Entering/exiting debug mode as well as
entering a low power mode will trigger a debug status message. Debug status information is sent out in the
following format:
Figure 25-31. Debug Status Message Format
25.11.12.2.6 Program Correlation Messages
Program correlation messages are used to correlate events to the program flow that may not be associated
with the instruction stream. In order to maintain accurate instruction tracing information when entering
debug mode or a CPU low power mode (where tracing may be disabled), this message is sent upon entry
into one of these two modes and includes the instruction count and branch history. Program correlation is
messaged out in the following format:
Figure 25-32. Program Correlation Message Format
msb lsb
234
RDATA RCODE (0001) SRC
4 bits
1
TCODE (011011)
4 bits1-32 bits 6 bits
Max length = 46 bits; Min length = 15 bits
STATUS [31:24]
msb lsb
12
SRC TCODE (000000)
3
6 bits4 bits8 bits
Fixed length = 18 bits
HIST
msb lsb
234
I-CNT EVCODE SRC
5
4 bits
1
TCODE (100001)
4 bits1-8 bits1-32 bits 6 bits
Max length = 54 bits; Min length = 16 bits
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