HP B1476 68020, User Manual, Page: 55 / 724

To break on an access to a variable
If you started the debugger using the Startall script, skip this section. Access
breakpoints are disabled because the analyzer has been configured to use the
Trig2 trigger for other purposes.
You can also set breakpoints on a read, a write, or any access of a variable.
This helps to locate defects due to multiple functions accessing the same
variable. Suppose you want to break on the access of the variable num_checks.
("&num_checks" should still be in the entry buffer.)
1 Set the breakpoint by selecting Breakpoints
→
Set
→
Read/Write () .
2 R un the program by clicking on the Run action key.
When the program stops, the code window shows that the program stopped at
the next reference to the variable num_checks. Due to the latency of the
emulation analyzer, the processor may halt up to two instruction cycles after
the breakpoint has been detected.
Try running the program a few more times to see where it stops. (Notice that
num_checks is passed by reference to interrupt_sim. Since counter points to the
same address as num_checks, the debugger stops at references to counter.)
3 Delete the access breakpoint. Select Window
→
Breakpoints, place the mouse
in the Breakpoint window, press and hold the right mouse button, and choose
Delete All Breakpoints.
Chapter 1: Getting Started with the Graphical Interface
To break on an access to a variable
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