7630 Datasheet, PDF (37/49 Pages) Renesas Technology Corp – SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER

MITSUBISHI MICROCOMPUTERS
7630 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
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0
A-D control register (address 0015₁₆)
ADCON
Analog input pin selection bits
b2 b1 b0
000:
001:
010:
011:
100:
101:
110:
111:
P0₀/AN₀
P0₁/AN₁
P0₂/AN₂
P0₃/AN₃
P0₄/AN₄
P0₅/AN₅
P0₆/AN₆
P0₇/AN₇
A-D conversion completion bit
0 : Conversion in progress
1 : Conversion completed
V_REF/Input switch bit
0 : Off
1 : On
Not used (“0” when read, do not write “1”)
Fig. 40 Structure of A-D control register
A-D Converter Operation
The comparator and control circuit reference an analog input volt-
age with the reference voltage, then stores the result in the A-D
conversion register. When an A-D conversion is complete, the con-
trol circuit sets the A-D conversion completion bit and the A-D inter-
rupt request bit to “1”. The result of A-D conversion can be obtained
from the A-D conversion register, AD (address 0014₁₆).
Note that the comparator is linked to a capacitor, so set f(X_IN) to 500
kHz or higher during A-D conversion.
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