Datasheet

Chapter 16 Debug Module (DBGV1)
MC9S12E128 Data Sheet, Rev. 1.07
Freescale Semiconductor 475
— Data associated with event B trigger modes
— Detail report mode stores address and data for all cycles except program (P) and free (f) cycles
— Current instruction address when in profiling mode
— BGND is not considered a change-of-flow (cof) by the debugger
16.1.2 Modes of Operation
There are two main modes of operation: breakpoint mode and debug mode. Each one is mutually exclusive
of the other and selected via a software programmable control bit.
In the breakpoint mode there are two sub-modes of operation:
• Dual address mode, where a match on either of two addresses will cause the system to enter
background debug mode (BDM) or initiate a software interrupt (SWI).
• Full breakpoint mode, where a match on address and data will cause the system to enter
background debug mode (BDM) or initiate a software interrupt (SWI).
In debug mode, there are several sub-modes of operation.
• Trigger modes
There are many ways to create a logical trigger. The trigger can be used to capture bus information
either starting from the trigger or ending at the trigger. Types of triggers (A and B are registers):
— A only
— A or B
— A then B
— Event only B (data capture)
— A then event only B (data capture)
— A and B, full mode
— A and not B, full mode
— Inside range
— Outside range
• Capture modes
There are several capture modes. These determine which bus information is saved and which is
ignored.
— Normal: save change-of-flow program fetches
— Loop1: save change-of-flow program fetches, ignoring duplicates
— Detail: save all bus operations except program and free cycles
— Profile: poll target from external device
16.1.3 Block Diagram
Figure 16-1 is a block diagram of this module in breakpoint mode. Figure 16-2 is a block diagram of this
module in debug mode.