
18 UART
18-2
EPSON
S1C17003 TECHNICAL MANUAL
18.2 UART Pin
Table 18.2.1 lists the UART input/output pins.
Table 18.2.1: UART pin list
Pin name
I/O
Qty
Function
SIN0 (P12)
I
1
UART Ch.0 data input pin
Inputs serial data sent from an external device.
SOUT0 (P11)
O
1
UART Ch.0 data output pin
Outputs serial data sent to an external device.
SCLK0 (P10)
I
1
UART Ch.0 clock input pin
Inputs the external clock when used for the transfer clock.
SIN1 (P30)
I
1
UART Ch.1 data input pin
Inputs serial data sent from an external device.
SOUT1 (P27)
O
1
UART Ch.1 data output pin
Outputs serial data sent to an external device.
SCLK1 (P16)
I
1
UART Ch.1 clock input pin
Inputs the external clock when used for the transfer clock.
The UART input/output pins (SINx, SOUTx, SCLKx) are shared with general purpose input/output port pins (P1[2:0],
P30, P27, P16) and are initially set as general purpose input/output port pins. The function must be switched using
the P3_PMUX, P2_PMUX, P1_PMUX register setting to use general purpose input/output port pins as UART
input/output pins. Switch the pins to serial interface mode by setting the following control bits to 1.
UART Ch.0
P12
→ SIN0
P12MUX: P12 Port Function Select Bit in the P1 Port Function Select (P1_PMUX) Register (D4/0x52a2)
P11
→ SOUT0
P11MUX: P11 Port Function Select Bit in the P1 Port Function Select (P1_PMUX) Register (D2/0x52a2)
P10
→ SCLK0 (only when using external clock)
P10MUX: P10 Port Function Select Bit in the P1 Port Function Select (P1_PMUX) Register (D0/0x52a2)
UART Ch.1
P30
→ SIN1
P30MUX: P30 Port Function Select Bit in the P3 Port Function Select (P3_PMUX) Register (D1-0/0x52a6)
P27
→ SOUT1
P27MUX: P27 Port Function Select Bit in the P2 Port Function Select (P2_PMUX) Register (D7-6/0x52a5)
P16
→ SCLK1 (only when using external clock)
P16MUX: P16 Port Function Select Bit in the P1 Port Function Select (P1_PMUX) Register (D5-4/0x52a3)
For detailed information on pin function switching, refer to “10.2 Input/output Pin Function Selection (Port
MUX).”