
R8C/36T-A Group
14. I/O Ports
Under development Preliminary document
Specifications in this document are tentative and subject to change.
R01UH0240EJ0010 Rev.0.10
Page 210 of 728
Aug 05, 2011
14.5.11 I/O Function Pin Select Register (PINSR)
XCSEL Bit (XCIN/XCOUT pin connect bit)
The XCSEL bit is used to select whether to assign XCIN and XCOUT to P4_3 and P4_4. If set to 0, XCIN is
not assigned to P4_3 and XCOUT is not assigned to P4_4. If set to 1, XCIN is assigned to P4_3 and XCOUT is
assigned to P4_4. Refer to 9. Clock Generation Circuit for information on how to set XCIN and XCOUT.
IOINSEL Bit (I/O port input function select bit)
When the PDi_j bit in the PDi register is 1 (output mode), the IOINSEL bit is used to select whether the value
read from the PORTi register is the port latch or the pin input level of the I/O port. If set to 0, the value of the
port latch is read. If set to 1, the pin input level of the I/O port is read.
Table 14.6 lists I/O Port Values Read by Using IOINSEL Bit. The IOINSEL bit can be used to change the input
function of all I/O ports.
i = 0 to 6, 8, j = 0 to 7
Address 002B9h
Bit
b7b6
b5b4b3
b2b1b0
Symbol
————
IOINSEL
——
XCSEL
After Reset
0
000
0000
Bit
Symbol
Bit Name
Function
R/W
b0
XCSEL
XCIN/XCOUT pin
connect bit
0: XCIN not connected to P4_3, XCOUT not connected to P4_4
1: XCIN connected to P4_3, XCOUT connected to P4_4
R/W
b1
—
Reserved
Set to 0.
R/W
b2
—
Nothing is assigned. The write value must be 0. The read value is 0.
—
b3
IOINSEL I/O port input function
select bit
0: The I/O port input function depends on the PDi (i = 0 to 6, 8)
register.
When the PDi_j (j = 0 to 7) bit in the PDi register is set to 0
(input mode), the pin input level can be read.
When the PDi_j bit in the PDi register is set to 1 (output
mode), the value of the port latch can be read.
1: The I/O port input function can read the pin input level
regardless of the PDi register
R/W
b4
—
Nothing is assigned. The write value must be 0. The read value is 0.
—
b5
—
b6
—
b7
—
Table 14.6
I/O Port Values Read by Using IOINSEL Bit
PDi_j Bit in PDi Register
0 (Input Mode)
1 (Output Mode)
IOINSEL bit
0
1
0
1
I/O port values read
Pin input level
Port latch value
Pin input level