Restrictions When Using The Demmuer; Keep The Demmuer Up To Date; The Target Program Is Interrupted While The Demmuer Is Being Loaded; The Analyzer Must Be Off - HP MC68040 User Manual

Chapter 10: Using Memory Management
Using the DeMMUer

Restrictions when using the deMMUer

Keep the deMMUer up to date

When you load the deMMUer, the emulator reads the present value of the TC, SRP,
and URP registers in the MMU, and the present translation tables, and calculates
the address translations that can be performed (all possible physical-to-logical
translations are determined during this process). Then the emulator loads the
deMMUer to reverse those translations. After the deMMUer is loaded, any change
to the MMU, its registers, or its translation tables will make the deMMUer out of
date. The only way to update the deMMUer for changes in the translation setup is
to load the deMMUer again.
The target program is interrupted while the deMMUer is
being loaded
The emulator uses the foreground monitor to load reverse translations into the
deMMUer. Depending on the complexity of your tables, this process can take a
long time. If there are portions of your target program that must not be interrupted
for long periods of time, make sure your code is executing in safe regions before
you load the deMMUer. You might set a breakpoint in a region of your target
program that is outside the time-critical regions and perform the load of the
deMMUer after the breakpoint is executed.

The analyzer must be off

Your analyzer must not be making a trace when you load the deMMUer.
Otherwise, part of the trace will be based on physical addresses and the other part
will be based on logical addresses.
Expect strange addresses if you analyze physical
memory with multiple logical mappings
The deMMUer can only translate a physical address into one logical address. If
two programs both use the same physical space (such as when two programs use a
single data location), they might refer to that space by two different logical address
values (and two different logical address symbols). The deMMUer translation
RAM will be loaded with only one of the logical addresses. This means that you
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