Epson S1C63454, Техническое руководство

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36
EPSON
S1C63454 TECHNICAL MANUAL
CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (I/O Ports)
4.6 I/O Ports (P00–P03 and P10–P13)
4.6.1 Configuration of I/O ports
The S1C63454 has eight bits of general-purpose I/O ports. Figure 4.6.1.1 shows the configuration of the I/
O port.
Address
Data
register
Data bus
P
XX
Address
Address
Address
I/O control
register (IOC)
Pull-up control
register (PUL)
Mask option
V
DD
Fig. 4.6.1.1 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.
When using the P10–P13 ports as the serial interface input/output terminals, the input specification of
the serial input terminals P10 and P12 (slave mode) can be selected from either "normal input" or "with
Schmitt trigger input" by mask option.
At initial reset, these terminals are all set to the I/O port.
Table 4.6.1.1 shows the setting of the input/output terminals by function selection.
Table 4.6.1.1 Function setting of input/output terminals
Terminal
P00–P03
P10
P11
P12
P13
Terminal status
at initial reset
P00–P03 (Input & pull-up
∗
)
P10 (Input & pull-up
∗
)
P11 (Input & pull-up
∗
)
P12 (Input & pull-up
∗
)
P13 (Input & pull-up
∗
)
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-up 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 4.11, "Serial Interface", for control of the serial interface.