12 i/O PORTS
12-2
Seiko epson Corporation
S1C63003/004/008/016 TeChniCal Manual
(Rev. 1.1)
1.1 Function settings of input/output terminals
Table 12.
Terminal
name
Terminal status
at initial reset
When special outputs/peripheral functions are used (selected by software)
Special output
Serial I/F
*
2
R/F
converter
Stopwatch
direct
input
*
2
Event
counter
TOUT
FOUT
BZ
Master
Slave
P00
P00 (IN & PD
*
1
)
RUN/STOP
P01
P01 (IN & PD
*
1
)
LAP
P02
P02 (IN & PD
*
1
)
P03
P03 (IN & PD
*
1
)
P10
P10 (IN & PD
*
1
)
EVIN_A
P11
P11 (IN & PD
*
1
)
TOUT_A
P12
P12 (IN & PD
*
1
)
BZ
P13
P13 (IN & PD
*
1
)
FOUT
P20–P21
P20–P21 (IN & PD
*
1
)
P22
P22 (IN & PD
*
1
)
EVIN_B
*
2
P23
P23 (IN & PD
*
1
)
TOUT_B
*
2
P30
*
2
P30 (IN & PD
*
1
)
SCLK(O)
SCLK(I)
P31
*
2
P31 (IN & PD
*
1
)
SOUT(O)
SOUT(O)
P32
*
2
P32 (IN & PD
*
1
)
SIN(I)
SIN(I)
P33
*
2
P33 (IN & PD
*
1
)
SRDY(O)/SS(I)
P40–P43
*
3
P40–P43 (IN & PD
*
1
)
P50
P50 (IN & PD
*
1
)
RFOUT
P51
P51 (IN & PD
*
1
)
SEN0
P52
P52 (IN & PD
*
1
)
REF0
P53
P53 (IN & PD
*
1
)
RFIN0
*
1: IN & PD (Input with pulled down): When "Pull-Down Used" is selected by mask option (high impedance when
"Pull-Down Not Used" is selected)
*
2: The P30 to P33 ports, serial interface, stopwatch direct input, TOUT_B output, and EVIN_B input functions are
not available in the S1C63003.
*
3: The P40 to P43 ports are not available in the S1C63003/004.
When these ports are used as I/O ports, the ports can be set to either input mode or output mode individually (in 1-bit
units). The mode can be set by writing data to the I/O control registers.
When the special output or peripheral function is used, the input/output direction of the port is automatically config-
ured by switching the terminal function and the I/O control registers becomes ineffective. For switching the terminal
function and input/output control, refer to respective peripheral circuit chapter.
Note: Before the port function is configured, the circuit that uses the port (e.g. input interrupt, multiple key
entry reset, serial interface, R/F converter, event counter input, direct RUN/LAP input for stopwatch)
must be disabled.
Mask Option
12.2
Output specification
The output specification of each I/O port during output mode can be selected from either complementary output
or P-channel open drain output by mask option. This selection can be done in 1-bit units. When P-channel open
drain output is selected, do not apply a voltage exceeding the power supply voltage to the port.
Pull-down resistor
The mask option also allows selection of whether the pull-down resistor is used or not during input mode. This
selection can be done in 1-bit units. When "Not use" is selected, take care that the floating status does not occur
during input mode.
The pull-down resistor for input mode and output specification (complementary output or P-channel open drain
output) selected by mask option are effective even when I/O ports are used for input/output of the serial interface
and R/F converter.
SeG outputs
The I/O ports P20–P53 input/output pins are shared with the SEG terminals. This mask option allows selection
of whether each of these pins are used for the I/O port or the SEG output. Refer to "Mask Option" in the "LCD
Driver" chapter for details.