mc68hc708mp16 Freescale Semiconductor, Inc, mc68hc708mp16 Datasheet - Page 340

• Manufacturer Part Number: mc68hc708mp16
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

External Interrupt (IRQ)
17.4 Functional Description
Technical Data
340
Addr.
$001E
IRQ1/V
PP
IRQ Status and Control
Name
Register (ISCR)
V
MODE1
DD
A logic 0 applied to any of the external interrupt pins can latch a CPU
interrupt request.
Interrupt signals on the IRQ1/V
interrupt latch remains set until one of the following actions occurs:
Figure 17-1. IRQ Module Block Diagram
•
•
•
D
Figure 17-2. IRQ I/O Register Summary
CK
LATCH
ACK1
IRQ1
CLR
Reset:
Read:
Write:
Vector fetch — A vector fetch automatically generates an interrupt
acknowledge signal that clears the latch that caused the vector
fetch.
Software clear — Software can clear an interrupt latch by writing
to the appropriate acknowledge bit in the interrupt status and
control register (ISCR). Writing a logic 1 to the ACK1 bit clears the
IRQ1 latch.
Reset — A reset automatically clears both interrupt latches.
Q
Bit 7
0
0
External Interrupt (IRQ)
Figure 17-1
6
0
0
IMASK1
SYNCHRO-
5
0
0
VOLTAGE
DETECT
NIZER
HIGH
shows the structure of the IRQ module.
PP
pin are latched into the IRQ1 latch. An
4
0
0
IRQ1F
3
0
MC68HC708MP16
Freescale Semiconductor
ACK1
2
0
0
IMASK1 MODE1
IRQ1
INTERRUPT
REQUEST
TO MODE
SELECT
LOGIC
1
0
—
Rev. 3.1
Bit 0
0