
46 Some
aspects
of
microprocessor design
Frame 3<
Frame 2
Frame 1
Empty cells f
Accumulator
program counter
Accumulator
program counter
Accumulator
program counter
Accumulator and program counter
of second-level interrupt routine,
stacked when third-level interruption
took place.
Accumulator and program counter of
first-level interrupt routine, stacked
when second-level interruption took
place.
Accumulator and program counter of
main program, stacked when first-
level interruption took place.
Figure 5.2
interruption, or 'interrupt', often comes from a peripheral device that
needs attention, and the section of program that provides that atten ...