Freescale Semiconductor Microcontrollers - Manual (Page 691)

ColdFire On-Chip DBG Module
Trigger Module Settings Window
691 Microcontrollers Debugger Manual
Figure 31.4 Trace Settings for Automatic mode
Sync PC DBG Feature
The Sync PC DBG feature forces the DBG module to capture the current program counter
at regular intervals and record this PC in the on-chip DBG buffer/FIFO. This is disabled
by default but is extremely useful when debugging program code loops without changes of
flow. When code loops are executed without traceable information, the DBG module does
not record any data, and the debugger cannot rebuild any program flow in the Trace
window.
To force the DBG module to capture program flow information regardless of the executed
instructions, engage the Sync PC feature using the list menu. The more cycles in the loop
you are debugging, the higher you can set the Sync PC cycle.
Figure 31.5 Sync PC List Menu
NOTE Engaging the Sync PC feature forces the on-chip DBG module to fill its
capture buffer/FIFO with data that is usually not necessary. Using this feature
automatically reduces the amount of change of flow information in the DBG
buffer/FIFO, and restricts program flow rebuild code range in the Trace
window.