HD404639R Datasheet, PDF (58/135 Pages) Renesas Technology Corp – 4-Bit Single-Chip Microcomputer

HD404639R Series
Compare enable register (CER: $018)
Bit
Initial value
Read/Write
Bit name
3
0
W
CER3
2
0
W
CER2
1
0
W
CER1
0
0
W
CER0
CER3
0
1
Digital/Analog selection
Digital input mode:
RD₀ /COMP₀ –RD₃ /COMP₃
operate as an R port.
Analog input mode:
RD₀ /COMP₀ –RD₃/COMP₃
operate as analog input.
CER1
0
0
1
1
CER0
0
1
0
1
Analog input pin selection
COMP₀
COMP₁
COMP₂
COMP₃
CER2
0
1
Reference voltage selection
External input voltage
Internal voltage
Figure 37 Compare Enable Register (CER)
Miscellaneous register (MIS: $00C)
Bit
Initial value
Read/Write
Bit name
3
0
W
MIS3
2
0
W
MIS2
1
0
W
MIS1
0
0
W
MIS0
MIS3
0
1
Pull-up and
pull-down MOS
on/off selection
Off
On
MIS2
0
1
PMOS transistor
on/off selection
for pin R4₃/SO₁
On
Off
MIS1
MIS0
t_RC selection.
Refer to figure 18 in the
operation modes section.
Figure 38 Miscellaneous Register (MIS)
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