Datasheet

Table Of Contents
External Interrupt (IRQ)
MC68HC908AB32Rev. 1.1 Technical Data
Freescale Semiconductor External Interrupt (IRQ)
341
NOTE: The interrupt mask (I) in the condition code register (CCR) masks all
interrupt requests, including external interrupt requests. (See 8.6
Exception Control.)
Figure 18-1. IRQ Module Block Diagram
ACK
IMASK
DQ
CK
CLR
IRQ
HIGH
INTERRUPT
TO MODE
SELECT
LOGIC
IRQ
FF
REQUEST
V
DD
MODE
VOLTAGE
DETECT
SYNCHRO-
NIZER
IRQF
TO CPU FOR
BIL/BIH
INSTRUCTIONS
VECTOR
FETCH
DECODER
INTERNAL ADDRESS BUS
RESET
V
DD
INTERNAL
PULLUP
DEVICE
IRQ
Addr.Register Name Bit 7654321Bit 0
$001A
IRQ Status and Control
Register
(ISCR)
Read: 0000IRQF0
IMASK MODE
Write:
ACK
Reset:00000000
= Unimplemented
Figure 18-2. IRQ I/O Register Summary