Z8S180 Zilog., Z8S180 Datasheet - Page 80

• Manufacturer Part Number: Z8S180
• Description: ENHANCED Z180 MICROPROCESSOR
• Manufacturer: Zilog.

Interrupts
Note:
Lower
Priority
The Z8X180 CPU has twelve interrupt sources, 4 external and 8 internal,
with fixed priority. (Reference Figure 31.)
This section explains the CPU registers associated with interrupt
processing, the TRAP interrupt, interrupt response modes, and the
external interrupts. The detailed discussion of internal interrupt
generation (except TRAP) is presented in the appropriate hardware
section (that is, PRT, DMAC, ASCI, and CSI/O).
Figure 31.
Interrupt Control Registers and Flags. The Z8X180 has three registers and
two flags which are associated with interrupt processing.
Higher
Priority
(10)
(11)
(12)
Packages not containing an A19 pin or situations using TOUT
instead of A18 yield an address capable of only addressing 512K
of physical space.
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
Interrupt Sources
TRAP (Undefined Op Code Trap)
NMI (Non Maskable Interrupt)
INT0 (Maskable Interrupt Level 0)
INT1 (Maskable Interrupt Level 1)
INT2 (Maskable Interrupt Level 2)
Timer 0
Timer 1
DMA channel 0
DMA channel 1
Clocked Serial I/O Port
Asynchronous SCI channel 0
Asynchronous SCI channel 1
M PU Us e r M anual
UM005001-ZMP0400
Internal Interrupt
Internal Interrupt
Z 8018x Fam il y
External Interrupt
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