M37632EFFP#U2 Renesas Electronics America, M37632EFFP#U2 Datasheet - Page 115

• Manufacturer Part Number: M37632EFFP#U2
• Description: IC 740 MCU 80QFP
• Manufacturer: Renesas Electronics America

Specifications of M37632EFFP#U2

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

4.3 Notes on interrupts
Fig. 4.3.1 Switching sequence of detection edge
Rev.2.00 Nov 14, 2006
REJ09B0322-0200
4.3.1 Setting for interrupt request bit and interrupt enable bit
To set an interrupt request bit and an interrupt enable bit for interrupts, execute as the
following sequence:
4.3.2 Switching of detection edge
If it is not necessary to generate interrupts synchronized with certain settings, such as
setting the active edge for external interrupts or switching the interrupt source for a vector
in cases where multiple interrupt sources are assigned to the same interrupt vector, use
the following procedure to make the settings.
The interrupt request bit may be set to “1” in the following cases:
• When switching the active edge for external interrupts.
• When switching the interrupt source for a vector in cases where multiple interrupt sources
are assigned to the same interrupt vector.
Reason
Reason
If the above setting are performed simultaneously with one instruction, an unnecessary
interrupt processing routine is executed. Because an interrupt enable bit is set to “1”
(interrupts enabled) before an interrupt request bit is cleared to “0.”
Clear an interrupt request bit to “0” (no interrupt request issued).
Set an interrupt enable bit to “1” (interrupts enabled).
C l e a r a n i n t e r r u p t r e q u e s t b i t t o “ 0 ” ( n o i n t e r r u p t r e q u e s t
i s s u e d )
C l e a r a n i n t e r r u p t e n a b l e b i t t o “ 0 ” ( i n t e r r u p t d i s a b l e d )
Set the interrupt edge selection bit (active edge switch
bit) or the interrupt (source) selection bit
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S e t t h e i n t e r r u p t e n a b l e b i t t o “ 1 ” ( i n t e r r u p t e n a b l e d )
NOP instruction (one or more instructions)
NOTES ON USE