Samsung S3F80JB manual P345CON Port345 Control Register E1H Set1 Bank1, P3.5 Mode Selection Bits

Models: S3F80JB

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S3F80JBCONTROL REGISTERS

P345CON — Port3[4:5] Control Register

E1H Set1 Bank1

Bit Identifier

Reset Value

Read/Write

Addressing Mode

.7 and .6

.7

.6

.5

.4

.3

.2

.1

.0

0

1

0

1

0

R/W

R/W

R/W

R/W

R/W

Register addressing mode only

 

 

 

 

 

P3.5 Mode Selection Bits

 

 

 

 

 

 

 

 

 

 

 

 

0 0

C-MOS input mode

 

 

 

 

 

01 Open-drain output mode

10 Push-pull output mode

1 1 C-MOS input with pull up mode

.5 and .4

P3.4 Mode Selection Bits

 

0

0

C-MOS input mode

 

 

 

 

 

0

1

Open-drain output mode

 

 

 

 

 

1

0

Push-pull output mode

 

1

1

C-MOS input with pull up mode

 

 

 

 

.3 and .1

.0

Not used for S3F80JB.

Port 4 Control Register Selection Bit

0P4CON Register selection

1P4CONH/P4CONL Register selection

NOTE: After CPU reset, P3.4 and P3.5 will be Open-drain output mode by the reset value of P345CON register at E1H, Set1, Bank1. P345CON will be initialized as “50h” to set P3.4 into the open-drain output mode after reset operation. Port4 control register P4CON will be selected by the reset value of P345CON.0 bit. If you use the Port4 input and output mode, set P345CON.0 to “1”.

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Samsung S3F80JB manual P345CON Port345 Control Register E1H Set1 Bank1, P3.5 Mode Selection Bits, P3.4 Mode Selection Bits