HD6475368CP Datasheet, PDF (68/108 Pages) Agilent(Hewlett-Packard) – H8/536 Emulator PC Interface

Enable Bus
Arbitration?
Note
The bus arbitration configuration question defines how your emulator
responds to bus request signals from the target system during
foreground operation. The /BREQ signal from the target system is
always ignored when the emulator is running the background monitor.
yes
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.
DMA (direct memory access) devices is prohibited from accessing to
emulation memory.
no
When you disable bus arbitration, 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 to check and see if faulty arbitration
circuitry in your target system is contributing to the problem.
4-8 Configuring the Emulator