R01UH0823EJ0100 Rev.1.00
Page 449 of 1823
Jul 31, 2019
RX23W Group
21. I/O Ports
21.4
Initialization of the Port Direction Register (PDR)
Initialize reserved bits in the PDR register according to
The blank columns in
indicate the bits corresponding to the pins listed in
The corresponding bits should be set to 1 (output) or 0 (input) depending on the user system.
However, the PORT3.PDR.B5 bit of the input-only P35 pin is reserved.
This bit should be set to 0 (input).
The columns other than the blank columns in
A reserved bit should be set to 0 (input) or 1 (output) according to
and
The B2 and B3 bits of PORT1.PDR, B0 bit of PORT2.PDR, and B2, B3, and B4 bits of PORT3.PDR register are
reserved. Values read from reserved bits are undefined. When writing, read the register and then rewrite the values
that were read to the reserved bit or bits.
When setting a value to a reserved bit, access in byte units.
x: Undefined
x: Undefined
Table 21.3
PDR Register Settings in 85-Pin Packages
Port Symbol
PDR Register
b7
b6
b5
b4
b3
b2
b1
b0
PORT0
1
1
1
1
1
PORT1
×
×
1
1
PORT2
1
1
×
PORT3
0
×
×
×
PORT4
PORTB
1
1
1
PORTC
1
PORTD
1
1
1
1
1
1
1
PORTE
1
1
1
PORTJ
1
1
1
1
1
1
1
Table 21.4
PDR Register Settings in 56-Pin Packages
Port Symbol
PDR Register
b7
b6
b5
b4
b3
b2
b1
b0
PORT0
1
1
1
1
1
1
1
PORT1
×
×
1
1
PORT2
1
1
1
1
1
×
PORT3
0
×
×
×
PORT4
1
1
1
1
PORTB
1
1
1
1
1
PORTC
1
PORTD
1
1
1
1
1
1
1
PORTE
1
1
1
1
1
PORTJ
1
1
1
1
1
1
1
1