CHAPTER 17 KEY INTERRUPT FUNCTION
Preliminary User’s Manual U16315EJ1V0UD
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17.3 Register Controlling Key Interrupt
(1) Key return mode register (KRM)
This register controls the KRM0 to KRM7 bits using the KR0 to KR7 signals, respectively.
This register is set by a 1-bit or 8-bit memory manipulation instruction.
RESET input clears this register to 00H.
Figure 17-2. Format of Key Return Mode Register (KRM)
KRM7
Does not detect key interrupt signal
Detects key interrupt signal
KRMn
0
1
Key interrupt mode control
KRM
KRM6
KRM5
KRM4
KRM3
KRM2
KRM1
KRM0
Address: FF6EH After reset: 00H R/W
Symbol
7
6
5
4
3
2
0
Cautions 1. If any of the KRM0 to KRM7 bits used is set to 1, set bits 0 to 7 (PU70 to PU77) of the
corresponding pull-up resistor register 7 (PU7) to 1.
2. If KRM is changed, the interrupt request flag may be set. Therefore, disable interrupts and
then change the KRM register. Clear the interrupt request flag and enable interrupts.
3. The bits not used in the key interrupt mode can be used as normal ports.