mc68hc908ld64 Freescale Semiconductor, Inc, mc68hc908ld64 Datasheet - Page 319

• Manufacturer Part Number: mc68hc908ld64
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

20.5 IRQ Status and Control Register (INTSCR)
MC68HC908LD64
Freescale Semiconductor
—
Rev. 3.0
Address:
The IRQ status and control register (INTSCR) controls and monitors
operation of the IRQ module. The INTSCR has the following functions:
IRQF — IRQ Flag
ACK — IRQ Interrupt Request Acknowledge Bit
IMASK — IRQ Interrupt Mask Bit
MODE — IRQ Edge/Level Select Bit
Reset:
Read:
Write:
•
•
•
•
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.
Figure 20-3. IRQ Status and Control Register (INTSCR)
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 flag
Clears the IRQ latch
Masks IRQ interrupt request
Controls triggering sensitivity of the IRQ interrupt pin
$001E
Bit 7
0
0
External Interrupt (IRQ)
= Unimplemented
6
0
0
5
0
0
4
0
0
IRQ Status and Control Register (INTSCR)
IRQF
3
0
ACK
2
0
0
External Interrupt (IRQ)
IMASK
1
0
Data Sheet
MODE
Bit 0
0
319