Z86L78 Datasheet, PDF (38/59 Pages) Zilog, Inc. – IR/Low-Voltage Microcontroller

Z86L78
IR/Low-Voltage Microcontroller
FUNCTIONAL DESCRIPTION (Continued)
Interrupts. The Z86L78 has five different interrupts, which
are maskable and prioritized (Figure 30). The five sources
are divided as follows: two are claimed by Port 3 lines P33,
P31, one by the low voltage detect circuit (IRQ0) and the
Zilog
remaining two by the counter/timers (Table 5). The Inter-
rupt Mask Register globally or individually enables or dis-
ables the five interrupt requests.
IRQ ^{IRQ0 IRQ2}
134
Interrupt
Edge
Select
IRQ Register (D6, D7)
IRQ
IMR
5
Interrupt
Request
Global
Interrupt
Enable
IPR
Priority
Logic
Vector Select
Figure 30. Interrupt Block Diagram
2-38
DS97LVO0701