HP 64746 User Manual page 157

Chapter 5: Plugging into a Target System
Configuring the Emulator for In-Circuit Operation
target system will at reset. Now you can simply set a breakpoint, and then run from
reset using the commands:
modify software_breakpoints enable <RETURN>
modify software_breakpoints set SWITCHED <RETURN>
run from reset <RETURN>
When the emulator breaks into the monitor, chip-select 0 will have been
programmed for address range 400000H through 41FFFFH and chip-select 1 will
have been programmed for address range 0 through 0FFFFH. Your program can
now modify RAM at address 0.
Note that an important limitation of this method is that if a target system reset
occurs while your program is running, the program will fail. This is because after a
reset, chip-select 0 will again map to address 0, but your code is no longer at
address 0. In order to put your code at 0, you would again need to issue the
command:
pod_command "cp 0=400000..401fff" <RETURN>
There are other ways that you can debug a system that reprograms the base
addresses of chip-selects. Another approach would be to debug your system in two
separate steps. First, you can debug your initialization code. Once your
initialization code is debugged, you can configure the emulator and map memory
based on what your final chip-select addresses will be. You can then use a
command file to set the chip-selects to their final addresses. This may require some
vector table changes.
Still another approach is to use only target memory in areas where chip-selects are
used. This doesn't require any special steps because your target memory will
"track" the chip-select changes.
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