MC68HC908AS60ACFN FREESCALE [Freescale Semiconductor, Inc], MC68HC908AS60ACFN Datasheet - Page 175

• Manufacturer Part Number: MC68HC908AS60ACFN
• Description: M68HC08 Microcontrollers
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

17.6 IRQ Status and Control Register
The IRQ status and control register (ISCR) controls and monitors operation of the IRQ module. The ISCR
has these functions:
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 high when the IRQ interrupt is pending.
Writing a logic 1 to this write-only bit clears the IRQ latch. ACK always reads as logic 0. Reset clears
ACK.
Writing a logic 1 to this read/write bit disables IRQ interrupt requests. Reset clears IMASK.
This read/write bit controls the triggering sensitivity of the IRQ pin. Reset clears MODE.
1 = IRQ interrupt pending
0 = IRQ interrupt not pending
1 = IRQ interrupt requests disabled
0 = IRQ interrupt requests enabled
1 = IRQ interrupt requests on falling edges and low levels
0 = IRQ interrupt requests on falling edges only
Shows the state of the IRQ interrupt flag
Clears the IRQ interrupt latch
Masks IRQ interrupt request
Controls triggering sensitivity of the IRQ interrupt pin
Address:
Reset:
Read:
Write:
MC68HC908AZ60A • MC68HC908AS60A • MC68HC908AS60E Data Sheet, Rev. 6
$001A
Bit 7
Figure 17-4. IRQ Status and Control Register (ISCR)
R
0
0
= Unimplemented
R
6
0
0
R
5
0
0
R
R
4
0
0
= Reserved
IRQF
3
0
ACK
2
0
0
IRQ Status and Control Register
IMASK
1
0
MODE
Bit 0
0
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