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FUJITSU F2MC-8L F202RA User Manual

Page 97

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81

CHAPTER 4 I/O PORTS

Table 4.2-3 lists the functions of the port 0 registers.

Port 0 pull-up setting register (PUL0)

The bits of the pull-up setting register correspond to the pins of port 0 in one-to-one correspondence. When

the pull-up resistor is selected by using the pull-up setting register, the pin will be at "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 4.2-2 shows the pull-up resistor settings assigned to the values of the bits of the port 0 pull-up

register.

Figure 4.2-2 Pull-up Resistor Settings (PUL0)

Table 4.2-3 Functions of Port 0 Registers

Register

name

Data

When being

read

When being written

Read/

Write

Address

Initial value

Port 0 data
register (PDR0)

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

0000

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 0 data
direction
register (DDR0)

0

Read
prohibited
(write only)

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

W

0001

H

00000000

B

1

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

R/W : Readable/Writable
W

: Write only

X

: Undefined

PUL03

PUL02

PUL01

PUL00

0

1

PUL07

PUL06

PUL05

PUL04

0

1

bit7

bit6

bit5

bit4

bit3

bit2

bit1

bit0

0070

H

PUL07 PUL06 PUL05 PUL04 PUL03 PUL02 PUL01 PUL00

00000000

B

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

Address

Initial value

P03 pull-up OFF

P02 pull-up OFF

P01 pull-up OFF

P00 pull-up OFF

P03 pull-up ON

P02 pull-up ON

P01 pull-up ON

P00 pull-up ON

P07 pull-up OFF

P06 pull-up OFF

P05 pull-up OFF

P04 pull-up OFF

P07 pull-up ON

P06 pull-up ON

P05 pull-up ON

P04 pull-up ON

: Readable/Writable

: Initial value

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