mc68hc908as60 Freescale Semiconductor, Inc, mc68hc908as60 Datasheet - Page 216

• Manufacturer Part Number: mc68hc908as60
• Description: Mc68hc908as60 Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

External Interrupt Module (IRQ)
16.4 Functional Description
Technical Data
IRQ
DECODER
VECTOR
FETCH
ACK1
A logic 0 applied to the external interrupt pin can latch a CPU interrupt
request.
Interrupt signals on the IRQ pin are latched into the IRQ1 latch. An
interrupt latch remains set until one of the following actions occurs:
•
•
•
Freescale Semiconductor, Inc.
For More Information On This Product,
V
MODE1
DD
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.
Figure 16-1. IRQ Block Diagram
Figure 16-1
D
CK
LATCH
External Interrupt Module (IRQ)
IRQ1
CLR
Go to: www.freescale.com
Q
shows the structure of the IRQ module.
IMASK1
SYNCHRO-
VOLTAGE
DETECT
NIZER
HIGH
MC68HC908AS60 — Rev. 1.0
IRQ1F
TO CPU FOR
BIL/BIH
INSTRUCTIONS
IRQ1
INTERRUPT
REQUEST
TO MODE
SELECT
LOGIC