HP 64783A, User Manual

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If you can’t break into the monitor after you
enable the MMU
Enter the commands: reset, and then break. If your MC68040 is now running in
the monitor, look at your MMU tables or the transparent translation register that
maintains 1:1 mapping for your foreground monitor. The mapping has failed.
Modify your MMU tables or the transparent translation register to obtain the 1:1
mapping for the address space occupied by the foreground monitor.
Refer to the end of Chapter 10, "Using Memory Management", for a detailed
example that discusses how to solve a "can’t break into monitor" problem.
If If the target system exhibits unexpected behavior
after executing a breakpoint
Normally when a software breakpoint instruction (BKPT) is executed, the
emulation processor generates a breakpoint acknowledge cycle as part of the
instruction. The emulator terminates the breakpoint acknowledge cycle and
initiates a transition into the monitor. Some target systems cannot tolerate this
behavior; they exhibit unexpected activity. When using such a target system,
configure the emulator to wait for the target system to terminate breakpoint
acknowledge cycles.
To configure the emulator to wait for the breakpoint acknowledge cycle to be
terminated by the target system, enter the command Settings
→
Pod Command
Keyboard. On the command line, enter the terminal interface command cf
bplock=en. Then press the suspend softkey. With this selection, the target
system is responsible for terminating breakpoint acknowledge cycles by asserting
TA or TEA. If the target system fails to provide the required cycle termination
signal, the processor will remain in a wait state indefinitely. Make sure your target
system provides the required cycle termination signal.
Emulators with serial prefix numbers below 3343A may not support this feature
even though they may appear to accept the bplock configuration item.
Chapter 9: Solving Problems
If you can’t break into the monitor after you enable the MMU
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