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

CHAPTER 19 INTERRUPT PIN SELECTION CIRCUIT
19.6

Precautions when Using Interrupt Pin Selection Circuit

This section explains the precautions to be taken when using the interrupt pin selection
circuit.
• WICR (interrupt pin control register) is initialized to "40
as an interrupt pin. If using pins other than the INT00 pin as external interrupt pins, update the value of
this register before enabling the operation of the external interrupt circuit.
• If more than one interrupt pin are selected in WICR (interrupt pin selection circuit control register)
simultaneously and the operation of INT00 (channel 0) of the external interrupt circuit is enabled (Set
the SL01 and SL00 bits of the EIC00 register to any value other than "00
circuit to select the valid edge. Also write "1" to the EIE0 bit to enable interrupts.), the selected pins will
remain enabled to perform input so as to accept interrupts even in a standby mode.
• If more than one interrupt pin are selected in WICR (interrupt pin selection circuit control register)
simultaneously, an input to INT00 (channel 0) of the external interrupt circuit is treated as "H" if any of
the selected input signals is "H". (It becomes "OR" of the signals inputted to the selected pins.)
326
" after a reset. This selects the INT00 bit only
H
" in the external interrupt
B