Using Software Breakpoints - HP 64751 User Manual

Using Software Breakpoints

Software breakpoints provide a way to accurately stop the execution of your
program at selected locations.
Note Version A.04.00 or greater of the HP 64700 system firmware provides support for
permanent as well as temporary breakpoints. If your version of HP 64700 system
firmware is less than A.04.00, only temporary breakpoints are supported.
When you set a software breakpoint at an address, the instruction at that address is
replaced with a BGND instruction. When the BGND instruction is executed,
control is passed to the emulator's monitor program, and the original instruction is
restored in the user program.
If the BGND instruction was not inserted as the result of a modify
software_breakpoints set command, the "Undefined software breakpoint"
message is displayed on the status line.
In order to successfully set a software breakpoint, the emulator must be able to
write to the memory location specified. Therefore, software breakpoints cannot be
set in target memory while the emulator is reset, and they can never be set in target
ROM. (You can, however, copy target ROM to emulation memory by storing the
contents of target ROM to an absolute file, re-mapping the range as emulation
RAM, and loading the absolute file.)
Another way to break user program execution at a certain point is to break on the
analyzer trigger.
This section shows you how to:
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Display the breakpoints list.
Enable/disable breakpoints.
Set a permanent breakpoint.
Set a temporary breakpoint.
Set all breakpoints.
Deactivate a breakpoint.
Chapter 6: Using the Emulator
Using Software Breakpoints
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