HP 68302 User Manual page 105

Chapter 4: Plugging the Emulator into Target Systems
Configuring the Emulator for In-Circuit Operation
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 since your
target memory will "track" the chip-select changes.
Step 4. Know your interrupt mode
If your target does not use dedicated mode interrupts, you can skip this step.
One of the more common problems users encounter is not being able to
break into the monitor (ERROR: break failed). A common cause of this is
selecting the dedicated interrupt mode in the emulator hardware
configuration, but failing to ensure that the 68302 is programmed for
dedicated mode interrupts.
The emulator is configured to use normal mode interrupts by default. If you
will be setting up the 68302 for dedicated mode interrupts, choose the
Settings→Emulator Config→ Hardware... (ALT, S, E, H) command and select
the dedicated Interrupt Mode option.
The interrupt mode of the 68302 is determined by the value programmed in
the GIMR register. If you are using dedicated mode interrupts, you must set
the most significant bit of the GIMR register BEFORE you attempt to step or
break. Similar to setting up chip-selects, you have two options for making
sure you have a valid interrupt mode:
Method 1: Using a Command File to Set the Interrupt Mode
Use a series of commands or a command file that modifies the GIMR to force
the 68302 to be in dedicated mode. For example, here is a command file that
sets up the GIMR for dedicated mode:
RESET
BREAK
REG bar TO 800h
REG gimr TO 8700h
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