Enabling Program Trace - STMicroelectronics SPC572L series Reference Manual

RM0400
Table 1104. Program Trace Exception Summary for w/Sync BTM messages
Exception Condition
Periodic Program Trace Sync.
Sequential Instruction Count
Overflow
Collision Priority
66.12.9

Enabling Program Trace

Program Trace Messaging can be enabled in one of three ways:
•
Setting the TM field of the DC1 Register to enable Program Trace
• Using the PTS field of the WT Register to enable Program Trace on Watchpoint hits
(watchpoints are configured within the CPU)
•
Using the external hardware trace enable input signal (nex_ptm_starttr)
•
Filtering of Program Trace messages may be performed using the MSR
setting of DC4
66.12.10 Program Trace Timing Diagrams (2 MDO / 1 MSEO configuration)
MCKO
MSEO_B
MDO[1:0] 00
A forced synchronization occurs periodically after 255 non-sync Program Trace
Messages have been queued. A Direct/Indirect Branch w/ Sync. Message is
queued. The periodic program trace message counter then resets.
After the sequential instruction counter reaches its maximum count (up to 255
sequential instructions may be executed), a forced synchronization occurs. The
sequential counter then resets. A Program Trace Direct/Indirect Branch w/
Sync.Message is queued upon execution of the next branch. A Resource Full
Message is Queued on the overflow event.
If a branch instruction is the 255th instruction to occur, and causes a Program
Trace message to be queued, then no Resource Full Message is queued, and the
w/Sync message will be queued for the next Program Trace Direct/Indirect Branch
Message.
All Messages have the following priority: Instruction 0 (WPM → DQM →
→OTM → BTM → DTM)→ Instruction1 (WPM → DQM → OTM →
PCM
PIDMSG
BTM → DTM), where instruction0 is the oldest instruction. A BTM Message from
Instruction1 that attempts to enter the queue at the same time as three higher
priority messages from either instruction will be lost. An Error Message will be sent
indicating the BTM was lost. The following direct/indirect branch will queue a
Direct/Indirect Branch w/ Sync. Message. The count value within this message will
reflect the number of sequential instructions executed after the last successful
BTM Message was generated. This count will include the branch that did not
generate a message due to the collision.
PTMARK
Figure 1171. Program Trace — Indirect Branch message (Traditional)
01 00 00
TCODE = 4
source processor = 0000
# of sequential instructions = 128
relative address = 8'ha5
DocID027809 Rev 4
Exception Handling
00 00 00 00
e200z215An3 Nexus 3 Module
10 01 01 10
bit and the
PMM
10 00
1959/2058
1982