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4 a/d enable register (aden), A/d enable register (aden) – FUJITSU F2MC-8L F202RA User Manual

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CHAPTER 12 A/D CONVERTER

12.4.4

A/D Enable Register (ADEN)

The ADEN register is used to select the analog input port that corresponds to different
pins. Writing "1" to an appropriate ADEN register bit enables analog input.

A/D Enable Register (ADEN)

Figure 12.4-5 shows the bit configuration of the A/D enable register.

Figure 12.4-5 A/D Enable Register (ADEN)

An A/D input port can be used as a general-purpose I/O port.

The ADEN register is used to select the port that corresponds to the analog input.

Set "1" to the corresponding bit in the ADEN register for the port to be used for analog input. This prevents

the DC pass when the middle level voltage is applied to the A/D input port.

When this register is to be used as the A/D input port, do not select the bit that indicates use of a pull-up

resistor from the pull-up setting register.

0

1

b

it7

b

it6

b

it5

b

it4

b

it

3

b

it2

b

it1

b

it0

00

3

4

H

ADE7

ADE6 ADE5

ADE4

ADE

3

ADE2

ADE1 ADE0

00000000

B

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W : Re

a

d

ab

le/Writ

ab

le

: Initi

a

l v

a

l

u

e

Addre

ss

Initi

a

l v

a

l

u

e

ADE7 to ADE0

A/D inp

u

t

b

it

s

Port inp

u

t

An

a

log inp

u

t

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