MC68HC08AS32 Datasheet, PDF (181/394 Pages) Motorola, Inc – M68HC08 Family of 8-bit microcontroller units (MCUs)

External Interrupt (IRQ)
IRQ Status and Control Register
Address: $001A
Bit 7
6
5
4
3
2
1
Bit 0
Read: 0
0
0
0
IRQF
0
IMASK MODE
Write: R
R
R
R
R
ACK
Reset: 0
0
0
0
0
0
0
0
R = Reserved
Figure 14-3. IRQ Status and Control Register (ISCR)
IRQF — IRQ Flag Bit
This read-only status bit is high when the IRQ interrupt is pending.
1 = IRQ interrupt pending
0 = IRQ interrupt not pending
ACK — IRQ Interrupt Request Acknowledge Bit
Writing a logic 1 to this write-only bit clears the IRQ latch. ACK always
reads as logic 0. Reset clears ACK.
IMASK — IRQ Interrupt Mask Bit
Writing a logic 1 to this read/write bit disables IRQ interrupt requests.
Reset clears IMASK.
1 = IRQ interrupt requests disabled
0 = IRQ interrupt requests enabled
MODE — IRQ Edge/Level Select Bit
This read/write bit controls the triggering sensitivity of the IRQ pin.
Reset clears MODE.
1 = IRQ interrupt requests on falling edges and low levels
0 = IRQ interrupt requests on falling edges only
MC68HC08AS32 — Rev. 3.0
MOTOROLA
External Interrupt (IRQ)
Advance Information
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