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FUJITSU F2MC-8L F202RA User Manual

Page 103

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CHAPTER 4 I/O PORTS

Table 4.3-3 lists the functions of port 3 registers.

Port 3 pull-up setting register (PUL3)

The bits of the pull-up setting register correspond to the pins of port 3 in one-to-one correspondence. When

the pull-up resistor is selected by using the pull-up setting register, the pin state will be "H" level (pull-up

state) instead of Hi-Z during stop (SPL = 1). During a reset, however, the pull-up is invalid and the pin

remains at Hi-Z.

Figure 4.3-2 shows the pull-up resistor settings assigned to the values of the bits of the port 3 pull-up

register.

Figure 4.3-2 Pull-up Setting Register (PUL3)

Table 4.3-3 Functions of Port 3 Registers

Register

name

Data

When being

read

When being written

Read/

Write

Address

Initial value

Port 3 data
register
(PDR3)

0

Pin state is
"L" level.

Output latch of "0" is set and
"L" level is output to the pin in
output port mode.

R/W

000C

H

XXXXXXXX

B

1

Pin state is
"H" level.

Output latch of "1" is set and
"H" level is output to the pin in
output port mode.

Port 3 data
direction
register
(DDR3)

0

Read
prohibited
(write only)

Output transistor operation is
disabled and the pin is set to
serve as an input pin.

W

000D

H

00000000

B

1

Output transistor operation is
enabled and the pin is set to
serve as an output pin.

R/W : Readable and Writable
W

: Write only

X

: Undefined

PUL33

PUL32

PUL31

PUL30

0

1

PUL37

PUL36

PUL35

PUL34

0

1

bit7

bit6

bit5

bit4

bit3

bit2

bit1

bit0

0071

H

PUL37 PUL36 PUL35 PUL34 PUL33 PUL32 PUL31 PUL30

00000000

B

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W : Readable and Writable

:

Initial value

Address

Initial value

P33 pull-up OFF

P32 pull-up OFF

P31 pull-up OFF P30 pull-up OFF

P33 pull-up ON

P32 pull-up ON

P31 pull-up ON

P30 pull-up ON

P37 pull-up OFF

P36 pull-up OFF P35 pull-up OFF

P34 pull-up OFF

P37 pull-up ON

P36 pull-up ON

P35 pull-up ON

P34 pull-up ON

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