M38203M4 Datasheet, PDF (116/344 Pages) Mitsubishi Electric Semiconductor – 8-BIT SINGLE-CHIP MICROCOMPUTER

APPLICATION
2.2 Interrupts
(2) Set values of Key input interrupt-related registers
When using the Key input interrupt, set the following:
qPort P2 direction register (address 000516)
qBit 2 of PULL register A (address 001616)
qBit 5 of interrupt request register 2 (address 003D16) = “0”
qBit 5 of interrupt control register 2 (address 003F16) (Note) = “1”
Figure 2.2.16 shows the setting values (corresponding to Figure 2.2.15) of the Key input interrupt-
related registers.
Note: Fix bit 7 of the interrupt control register 2 (address 003F16) to “0.”
b7
b0
1 1 1 1 0 0 0 0 _{Port P2 direction register [Address 0516]}
Bits corresponding to P20–P27
0 : Input port
1 : Output port
b7
b0
1
PULL register A [Address 1616]
P20–P27 pull-up
0 : No pull-up
1 : Pull-up
b7
0
b0
Interrupt request register 2 [Address 3D16]
Key input interrupt request bit
0 : No interrupt request issued
1 : Interrupt request issued
b7
01
b0
Interrupt control register 2 [Address 3F16]
Key input interrupt enable bit
0 : Interrupts disabled
1 : Interrupts enabled
: “0” or “1.”
Fig. 2.2.16 Setting values (corresponding to Figure 2.2.15) of key input interrupt-related registers
2–30
3820 GROUP USER’S MANUAL