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EPSON
S1C63666 TECHNICAL MANUAL
CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (I/O Ports)
4.7 I/O Ports (P00–P03 and P10–P13)
4.7.1 Configuration of I/O ports
The S1C63666 has eight bits of general-purpose I/O ports. Figure 4.7.1.1 shows the configuration of the I/
O port.
Address
Data
register
Data bus
Pxx
Address
Address
Address
I/O control
register (IOC)
Pull-down control
register (PUL)
Mask
option
V
SS
Fig. 4.7.1.1 Configuration of I/O port
The I/O port terminals P10 to P13 are shared with the serial interface input/output terminals. The
software can select the function to be used.
At initial reset, these terminals are all set to the I/O port.
Table 4.7.1.1 shows the setting of the input/output terminals by function selection.
Table 4.7.1.1 Function setting of input/output terminals
Terminal
P00–P03
P10
P11
P12
P13
Terminal status
at initial reset
P00–P03 (Input & pull-down
∗
)
P10 (Input & pull-down
∗
)
P11 (Input & pull-down
∗
)
P12 (Input & pull-down
∗
)
P13 (Input & pull-down
∗
)
Serial I/F
Master
Slave
P00–P03 P00–P03
SIN(I)
SIN(I)
SOUT(O) SOUT(O)
SCLK(O) SCLK(I)
P13
SRDY(O)
∗
When "with pull-down resistor" is selected by the mask option
(high impedance when "gate direct" is set)
When these ports are used as I/O ports, the ports can be set to either input mode or output mode indi-
vidually (in 1-bit unit). Modes can be set by writing data to the I/O control registers.
Refer to Section 4.12, "Serial Interface", for control of the serial interface.
