HD404374 Datasheet, PDF (66/161 Pages) Renesas Technology Corp – Low-Voltage AS Microcomputers with On-Chip A/D Converter

HD404374/HD404384/HD404389/HD404082/HD404084 Series
Bit 2 of the miscellaneous register must always be set to 0. The microcomputer will malfunction
if it is set to 1.
Miscellaneous register (MIS: $005)
Bit
Read/Write
3
2
1
0
W
W
W
W
Initial value on reset
Bit name
0
MIS3
0
Not used^*
0
MIS1
0
MIS0
MIS2
0
1
Setting bit2
Set to 0
Use prohibited
tRC selection
(See figure 15 in the
Operating Modes section)
MIS3
0
1
pull-up MOS control
All pull-ups MOS off
pull-up MOS active
Note: * This bit must always be set to 0. The microcomputer will malfunction if it is set to 1.
Figure 30 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.
Rev.5.00, Sep.11.2003, page 66 of 161