4513_03 Datasheet, PDF (111/210 Pages) Renesas Technology Corp – 4-BIT SINGLE-CHIP MICROCOMPUTER

APPLICATION
2.1 I/O pins
Switching key input selection port (D₀→D₁)
Stabilizing wait time for input
Reading port (key input)
D0 ^{“H”}
“L”
D1 ^{“H”}
“L”
D2 ^{“H”}
“L”
D3 ^{“H”}
“L”
Key input period
IAP0
IAP0
IAP0
IAP0
IAP0
Input to
SW1–SW4
Input to
SW5–SW8
Input to
Input to
SW9–SW12 SW13–SW16
Input to
SW1–SW4
Note: “H” output of port D becomes high-impedance state.
Fig. 2.1.2 Key scan input timing
2-8
4513/4514 Group User’s Manual