7- 30 M68040 USER’S MANUAL MOTOROLA
SAMPLE AND SYNCHRONIZE
INTERRUPT LEVEL I2–I0,
OR TRANSITION ON LEVEL 7
Figure 7-19. Interrupt Pending Procedure
The M68040 asserts IPEND when an interrupt request is pending. Figure 7-20 illustrates
the assertion of IPEND relative to the assertion of an interrupt level on the IPL≈ signals.
IPEND signals external devices that an interrupt exception will be taken at an upcoming
instruction boundary (following any higher priority exception). The IPEND signal negates
after the processor recognizes the internal interrupt acknowledge and can precede the
external interrupt acknowledge bus cycle.
COMPARE REQUEST WITH MASK IN SR
ASSERT IPENDIPLs RECOGNIZED
Figure 7-20. Assertion of