Precautions When Using External Interrupt Circuit - Fujitsu F2MC-8FX Hardware Manual

18.7

Precautions when Using External Interrupt Circuit

This section describes the precautions that must be followed when using the external
interrupt circuit.
Precautions when Using External Interrupt Circuit
• Set the interrupt request enable bit (EIE) to "0" (disabling interrupt requests) when setting the edge
polarity select bit (SL).
Also clear the external interrupt request flag bit (EIR) to "0" after setting the edge polarity.
• The operation cannot recover from the interrupt processing routine if the external interrupt request flag
bit is "1" and the interrupt request enable bit is enabled. Always clear the external interrupt request flag
bit in the interrupt processing routine.
CHAPTER 18 EXTERNAL INTERRUPT CIRCUIT
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