NEC PD750008 User Manual
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CHAPTER 6 INTERRUPT AND TEST FUNCTIONS
(2) INT2 and key interrupt (KR0 to KR7) hardware
Figure 6-10 shows the configuration of INT2 and KR0 to KR7.
The IRQ2 set signal is output in either of the following edge detection modes, which is selected with the
INT2 edge detection mode register (IM2).
(a) Detection of a rising edge on the INT2 input pin
IRQ2 is set when a rising edge is detected on the INT2 input pin.
(b) Detection of a falling edge on any of the KR0 to KR7 input pins (key interrupt)
One of the pins KR0 to KR7 is selected to be used for interrupt input with the INT2 edge detection
mode register (IM2). When a falling edge of one of input signals applied to the selected pin is detected,
IRQ2 is set.
Figure 6-11 shows the format of IM2. IM2 is set using a 4-bit manipulation instruction. When the RESET
signal is generated, all bits are cleared to 0, and the rising edge on INT2 is specified.