178
Bit 1:
TXD
31
pin output data inversion switch
Bit 1 specifies whether or not TXD
31
pin output data is to be inverted.
Bit 1
SCINV1
Description
0
TXD
31
output data is not inverted
TXD
31
output data is inverted
(initial value)
1
Bit 0:
RXD
31
pin input data inversion switch
Bit 0 specifies whether or not RXD
31
pin input data is to be inverted.
Bit 0
SCINV0
Description
0
RXD
31
input data is not inverted
RXD
31
input data is inverted
(initial value)
1
8.13.3
Note on Modification of Serial Port Control Register
When a serial port control register is modified, the data being input or output up to that point is
inverted immediately after the modification, and an invalid data change is input or output. When
modifying a serial port control register, do so in a state in which data changes are invalidated
8.14
Application Note
8.14.1
The Management of the Un-Use Terminal
If an I/O pin not used by the user system is floating, pull it up or down.
If an unused pin is an input pin, handle it in one of the following ways:
Pull it up to V
CC
with an on-chip pull-up MOS.
Pull it up to V
CC
with an external resister of approximately 100 k
.
Pull it down to V
SS
with an external resister of approximately 100 k
.
If an unused pin is an output pin, handle it in one of the following ways:
Set the output of the unused pin to high and pull it up to V
CC
with an on-chip pull-up MOS.
Set the output of the unused pin to high and pull it up to V
CC
with an external resister of
approximately 100 k
.
Set the output of the unused pin to low and pull it down to V
SS
with an external resister of
approximately 100 k
.