E202075_HD404889 Datasheet, PDF (80/202 Pages) Renesas Technology Corp – Low-Voltage AS Microcomputers with On-Chip LCD Circuit

HD404889/HD404899/HD404878/HD404868 Series
Miscellaneous register (MIS: $005)
Bit
Read/Write
3
2
W
—
Initial value on reset
0
—
Bit name
MIS3
—
1
W
0
MIS1
0
W
0
MIS0
MIS3
0
1
pull-up MOS control
All pull-ups MOS off
pull-up MOS active
tRC selection
(See figure 17 in the
Operating Modes section)
Figure 33 Miscellaneous Register (MIS:$005)
Handling of I/O Pins Not Used by User System
If I/O pins that are not used by the user system are left floating, they may generate noise that can result in
chip malfunctions. Therefore, the pin potential must be fixed.
In this case, pull the pins up to V_CC with the built-in pull-up MOS or with an external resistor of
approximately 100 kΩ.
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