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note: Ch.0 and Ch.1 have the same configuration and the same function (except for ISO7816 mode in
Ch.1). The signal and control bit names are suffixed by a 0 or 1 to indicate the channel number, en-
abling discrimination between channels 0 or 1. In this manual, however, channel numbers 0 or 1 are
replaced with ‘x’ unless discrimination is necessary, because explanations are common to all three
channels.
V.1.1.2 i/o Pins of serial interface
Table V.1.1.2.1 lists the I/O pins used by the serial interface.
Table V.1.1.2.1 Serial-Interface Pin Configuration
Pin name
SIN0
SOUT0
#SCLK0
#SRDY0
SIN1
SOUT1
#SCLK1
#SRDY1
i/o
I
O
I/O
I
O
I/O
Function
Serial I/F Ch.0 data input
Serial I/F Ch.0 data output
Serial I/F Ch.0 clock input/output
Serial I/F Ch.0 ready input/output
Serial I/F Ch.1 data input
Serial I/F Ch.1 data output
Serial I/F Ch.1 clock input/output
Serial I/F Ch.1 ready input/output
sinx (serial-data input pin)
This pin is used to input serial data to the device.
soutx (serial-data output pin)
This pin is used to output serial data from the device.
#sCLKx (clock input/output pin)
This pin is used to input or output a clock.
In clock-synchronized slave mode, it is used as a clock input pin; in clock-synchronized master mode and
ISO7816 mode (Ch.1), it is used as a clock output pin.
In asynchronous mode, this pin is used as clock input when an external clock is used. This pin is not used when
the internal clock is used, so it can be used as an I/O port.
#sRDYx (ready-signal input/output pin)
This pin is used to input or output the ready signal that is used in clock-synchronized mode.
In clock-synchronized slave mode, it is used as a ready-signal output pin; in clock-synchronized master mode,
it is used as a ready-signal input pin.
This pin is not used in asynchronous mode and ISO7816 mode (Ch.1), so it can be used as an I/O port.
note: The serial interface input/output pins are shared with general-purpose I/O ports or other periph-
eral circuit inputs/outputs, so that functionality in the initial state is set to other than the serial
interface input/output. Before the serial interface input/output signals assigned to these pins can
be used, the function of these pins must be switched for the serial interface input/output by setting
the corresponding Port Function Select Registers.
For details of pin functions and how to switch over, see Section I.3.3, “Switching Over the Multi-
plexed Pin Functions.”