HP 64783A, Руководство пользователя

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To select the monitor interrupt priority level
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Type in the desired interrupt priority level for your foreground monitor in the text
entry area beside "Interrupt Priority Level".
Enter a number from 0 to 7 in the text entry area. This is the interrupt priority level
that will be held off by the emulation monitor during monitor execution. Interrupts
having values higher than the number you enter here will be recognized by the
processor.
Set the interrupt priority level low enough to allow your target system to function
correctly, but high enough to avoid excessive interrupt processing. The default
value of 0 allows all target system interrupts to be recognized by the foreground
monitor.
The emulator uses a level 7, non-maskable interrupt to interrupt the target system
and break into the monitor. When the foreground monitor is not executing critical
code (such as monitor entry and exit), the foreground monitor will set the interrupt
priority mask to the value you enter beside "Interrupt Priority Level", or to the
interrupt level that was in effect before monitor entry, whichever is greater.
Example Suppose your target system has a disk device driver that uses interrupt level 5, and
the service routine must be run to prevent target system damage. To allow
interrupts of higher priority than level 4 to be serviced during foreground monitor
execution, enter 4 beside "Interrupt Priority Level". In this case, all interrupts with
values of 4 or less will be ignored when the foreground monitor is executing.
Chapter 8: Configuring the Emulator
Modifying the Monitor Setup
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