Specifications
36 EPSON S1C6P466 TECHNICAL MANUAL
CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (I/O Ports)
4.6 I/O Ports (P00–P03, P10–P13 and P20–P23)
4.6.1 Configuration of I/O ports
The S1C6P466 has 12 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)
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 P22
and P23 terminals are shared with the special output (CL, FR) terminals. The software can select the
function to be used. At initial reset, these 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
P20
P21
P22
P23
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)
P20 (Input & pull-up)
P21 (Input & pull-up)
P22 (Input & pull-up)
P23 (Input & pull-up)
Special output
CL FR
P00–P03P00–P03
P20 P20
P21 P21
CL
FR
Serial I/F
Master Slave
P00–P03 P00–P03
SIN(I) SIN(I)
SOUT(O) SOUT(O)
SCLK(O) SCLK(I)
P13 SRDY(O)
P20 P20
P21 P21
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.
4.6.2 Mask option
In the S1C6P466, the I/O port specification is fixed at "with pull-up resistor" and "complementary
output".