MC68HC711D3CFB2 FREESCALE [Freescale Semiconductor, Inc], MC68HC711D3CFB2 Datasheet - Page 17

• Manufacturer Part Number: MC68HC711D3CFB2
• Description: Microcontrollers
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

1.9 Interrupt Request (IRQ)
The IRQ input provides a means of applying asynchronous interrupt requests to the microcontroller unit
(MCU). Either negative edge-sensitive triggering or level-sensitive triggering is program selectable by
using the IRQE bit of the OPTION register. IRQ is always configured to level-sensitive triggering at reset.
While the programmable read-only memory (PROM) is being programmed, this pin provides the chip
enable (CE) signal. To prevent accidental programming of the PROM during reset, an external resistor is
required on IRQ to pull the pin to V
Freescale Semiconductor
*
FIRST MCU
Values includes all stray capacitances.
MCU
MCU
EXTAL
EXTAL
EXTAL
XTAL
XTAL
XTAL
10K–100K
10 M
10 M
NC OR
LOAD
Figure 1-5. Oscillator Connections
CRYSTAL
CRYSTAL
DD
MC68HC711D3 Data Sheet, Rev. 2.1
.
4 x E
4 x E
4 x E
CMOS-COMPATIBLE
EXTERNAL OSCILLATOR
25 pF *
25 pF *
25 pF *
25 pF *
10K–100K
NC OR
LOAD
SECOND MCU
EXTAL
XTAL
Interrupt Request (IRQ)
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