Selecting I/O Pin Functions (Port Mux) - Epson S1C17704 Technical Manual

10 I/O PORTS (P)

10.2 Selecting I/O Pin Functions (Port MUX)

The I/O port pins, except for some I/O ports, are shared with internal peripheral modules. Whether they are used as
I/O ports or for peripheral modules can be selected using the port function select bit corresponding to each I/O port.
All pins not used for peripheral modules can be used as general-purpose I/O ports.
Pin function 1
PxxMUX = 0
P00 –
P01 –
P02 –
P03 –
P04
REMI (REMC)
P05 REMO (REMC)
P06/EXCL2 (T16CH2) –
P07/EXCL1 (T16CH1) –
P10
–
P11 –
P12 –
P13 FOUT1 (OSC)
P14
SDA (I2C)
P15 SCL (I2C)
P16/EXCL0 (T16CH0) –
P17 #SPISS (SPI)
P20
SDI (SPI)
P21 SDO (SPI)
P22 SPICLK (SPI)
P23 SIN (UART)
P24 SOUT (UART)
P25
SCLK (UART)
P26 TOUT (T16E)
P27 EXCL3 (T16E)
P30 FOUT3 (OSC)
DCLK (DBG)
P31
DST2 (DBG) P32
DSIO (DBG) P33
At initial reset, each I/O port pin (Pxx) is initialized for the default function ("Pin function 1" in Table 10.2.1).
The P06, P07, and P16 pins can be used as the external clock input pins for the 16-bit timer by setting the ports in
input mode. However, general-purpose I/O function is also effective in this case, so no port function select bit is
provided.
For the pin function other than the I/O port, see the descriptions for the peripheral module indicated in ( ).
The subsequent sections explain the port functions assuming that the pin has been set for the general-purpose I/O
port.
10-2
Table 10.2.1 Selecting I/O Pin Functions
Pin function 2 Port function
PxxMUX = 1 select bit
–
–
–
–
P04MUX (D4) P0 Port Function Select (P0_PMUX) Register (0x52a0)
P05MUX (D5)
–
–
–
–
–
P13MUX (D3) P1 Port Function Select (P1_PMUX) Register (0x52a1)
P14MUX (D4)
P15MUX (D5)
–
P17MUX (D7) P1 Port Function Select (P1_PMUX) Register (0x52a1)
P20MUX (D0) P2 Port Function Select (P2_PMUX) Register (0x52a2)
P21MUX (D1)
P22MUX (D2)
P23MUX (D3)
P24MUX (D4)
P25MUX (D5)
P26MUX (D6)
P27MUX (D7)
P30MUX (D0) P3 Port Function Select (P3_PMUX) Register (0x52a3)
P31MUX (D1)
P32MUX (D2)
P33MUX (D3)
–
–
–
–
–
–
–
–
–
–
EPSON
Control register
S1C17704 TECHNICAL MANUAL