S908AC4MDRE FREESCALE [Freescale Semiconductor, Inc], S908AC4MDRE Datasheet - Page 83

• Manufacturer Part Number: S908AC4MDRE
• Description: M68HC08 Microcontrollers
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

7.7 I/O Signals
The IRQ module does not share its pin with any module on this MCU.
7.7.1 IRQ Input Pins (IRQ)
The IRQ pin provides a maskable external interrupt source. The IRQ pin contains an internal pullup
device.
7.8 Registers
The IRQ status and control register (INTSCR) controls and monitors operation of the IRQ module. The
INTSCR:
IRQF — IRQ Flag Bit
ACK — IRQ Interrupt Request Acknowledge Bit
IMASK — IRQ Interrupt Mask Bit
MODE — IRQ Edge/Level Select Bit
Freescale Semiconductor
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This read-only status bit is set when the IRQ interrupt is pending.
Writing a 1 to this write-only bit clears the IRQ latch. ACK always reads 0.
Writing a 1 to this read/write bit disables the IRQ interrupt request.
This read/write bit controls the triggering sensitivity of the IRQ pin.
1 = IRQ interrupt pending
0 = IRQ interrupt not pending
1 = IRQ interrupt request disabled
0 = IRQ interrupt request enabled
1 = IRQ interrupt request on falling edges and low levels
0 = IRQ interrupt request on falling edges only
Shows the state of the IRQ flag
Clears the IRQ latch
Masks the IRQ interrupt request
Controls triggering sensitivity of the IRQ interrupt pin
Reset:
Read:
Write:
MC68HC908QC16 • MC68HC908QC8 • MC68HC908QC4 Data Sheet, Rev. 5
Bit 7
0
0
Figure 7-3. IRQ Status and Control Register (INTSCR)
= Unimplemented
6
0
0
5
0
0
4
0
0
IRQF
3
0
ACK
2
0
0
IMASK
1
0
MODE
Bit 0
0
I/O Signals
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