M37212 Mitsubishi, M37212 Datasheet - Page 49

• Manufacturer Part Number: M37212
• Description: SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER for VOLTAGE SYNTHESIZER
• Manufacturer: Mitsubishi

8.8 A-D COMPARATOR
A-D comparator consists of 6-bit D-A converter and comparator. A-D
comparator block diagram is shown in Figure 8.8.1.
The reference voltage “V
the A-D control register (address 00EF
The comparison result of the analog input voltage and the reference
voltage “V
00EE
For A-D comparison, set “0” to corresponding bits of the direction
register to use ports as analog input pins. Write the data for select of
analog input pins to bits 0 to 2 of the A-D control register 1 and write
the digital value corresponding to V
to 5 of the A-D control register. The voltage comparison starts by
writing to the A-D control register 2, and it is completed after 16 ma-
chine cycles (NOP instruction
Fig. 8.8.1 A-D Comparator Block Diagram
Rev. 1.0
16
A - D m o d e r e g i s t e r
).
ref
A - D 1
A - D 2
A - D 3
A - D 4
A - D 5
A - D 6
A - D 7
A - D 8
” is stored in bit 4 of the A-D mode register (address
B i t s 0 t o 2
A n a l o g
s i g n a l
s w i t c h
ref
” for D-A conversion is set by bits 0 to 5 of
8).
ref
C o m p a r a t o r c o n t r o l
16
to be compared to the bits 0
).
C o m p a -
r a t o r
M37212M4/M8–XXXSP, M37212M6–XXXSP/FP
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER for VOLTAGE SYNTHESIZER
B i t 4
D a t a b u s
A - D m o d e
r e g i s t e r
B i t 5
B i t 4
with ON-SCREEN DISPLAY CONTROLLER
B i t 3
MITSUBISHI MICROCOMPUTERS
R e s i s t o r l a d d e r
S w i t c h t r e e
A - D c o n t r o l
r e g i s t e r
M37212EFSP/FP
B i t 2
B i t 1
B i t 0
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