HP H8/3003, User Manual

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cf ba
The ba (bus arbitration) configuration item defines how your emulator
responds to bus request signals from the target system.
M> cf ba=en
When bus arbitration is enabled, the /BREQ (bus request) signal from
the target system is responded to exactly as it would be if only the
emulation processor was present without an emulator. In other words, if
the emulation processor receives a /BREQ from the target system, it
will respond by asserting /BACK and will set the various processor
lines to tri-state. /BREQ is then released by the target; /BACK is
negated by the processor, and the emulation processor restarts
execution.
M> cf ba=dis
When you disable bus arbitration by entering the above command, the
emulator ignores the /BREQ signal from the target system. The
emulation processor will never drive the /BACK line true; nor will it
place the address, data and control signals into the tri-state mode.
Enabling and disabling bus master arbitration can be useful to you in
isolating target system problems. For example, you may have a
situation where the processor never seems to execute any code. You
can disable bus arbitration using cf ba=dis to check and see if faulty
arbitration circuitry in your target system is contributing to the problem.
Note
When bus arbitration is enabled, the emulator responds to /BREQ
signal during both foreground and background operation.
Note The commands which cause the emulator to break to monitor are
ignored during the processor releases bus cycles.
4-4 Configuring the Emulator