III PERIPHERAL BLOCK: INPUT/OUTPUT PORTS

I/O Ports (P Ports)

Structure of I/O Port

The Peripheral Block contains 29 bits of I/O ports (P00 to P05, P10 to P16, P20 to P27, P30 to P35) that can be directed for input or output through the use of a program.

Figure 9.2 shows the structure of a typical I/O port.

Internal data bus

VDDE

I/O control

register

Function

select register

Data

Pxx

 

register

 

Peripheral circuit output

VSS

Peripheral circuit

input

Figure 9.2 Structure of I/O Port

I/O Port Pins

The I/O ports concurrently serve as the input/output pins for peripheral circuits, as shown in Table 9.3.Whether they are used as I/O ports or for peripheral circuits can be set bit-for-bit using a function select register. All pins not used for peripheral circuits can be used as general-purpose I/O ports.

Table 9.3 I/O Pins

Pin name

 

I/O

Pull-up

Function

Function select bit

P00/SIN0

 

I/O

–

I/O port / Serial IF Ch.0 data input

CFP00(D0)/P0 function select register(0x402D0)

P01/SOUT0

 

I/O

–

I/O port / Serial IF Ch.0 data output

CFP01(D1)/P0 function select register(0x402D0)

P02/#SCLK0

 

I/O

–

I/O port / Serial IF Ch.0 clock input/output

CFP02(D2)/P0 function select register(0x402D0)

P03/#SRDY0

 

I/O

–

I/O port / Serial IF Ch.0 ready input/output

CFP03(D3)/P0 function select register(0x402D0)

P04/SIN1

 

I/O

–

I/O port / Serial IF Ch.1 data input

CFP04(D4)/P0 function select register(0x402D0)

 

 

 

 

 

CFEX4(D4)/Port function extension register(0x402DF)

P05/SOUT1

 

I/O

–

I/O port / Serial IF Ch.1 data output

CFP05(D5)/P0 function select register(0x402D0)

 

 

 

 

 

CFEX5(D5)/Port function extension register(0x402DF)

P10/EXCL0/

 

I/O

–

I/O port / 16-bit timer 0 event counter input (I) /

CFP10(D0)/P1 function select register(0x402D4)

T8UF0/DST0

∗

 

 

8-bit timer 0 output (O) / DST0 output (Ex)

CFEX1(D1)/Port function extension register(0x402DF)

P11/EXCL1/

 

I/O

–

I/O port / 16-bit timer 1 event counter input (I) /

CFP11(D1)/P1 function select register(0x402D4)

T8UF1/DST1

∗

 

 

8-bit timer 1 output (O) / DST1 output (Ex)

CFEX1(D1)/Port function extension register(0x402DF)

P12/EXCL2/

 

I/O

–

I/O port / 16-bit timer 2 event counter input (I) /

CFP12(D2)/P1 function select register(0x402D4)

T8UF2/DST2

∗

 

 

8-bit timer 2 output (O) / DST2 output (Ex)

CFEX0(D0)/Port function extension register(0x402DF)

P13/EXCL3/

 

I/O

–

I/O port / 16-bit timer 3 event counter input (I) /

CFP13(D3)/P1 function select register(0x402D4)

T8UF3/DPCO

∗

 

 

8-bit timer 3 output (O) / DPCO output (Ex)

CFEX1(D1)/Port function extension register(0x402DF)

P14/FOSC1/

 

I/O

–

I/O port / Low-speed (OSC1) clock output /

CFP14(D4)/P1 function select register(0x402D4)

DCLK

∗

 

 

DCLK output (Ex)

CFEX0(D0)/Port function extension register(0x402DF)

P15/EXCL4/

 

I/O

–

I/O port / 16-bit timer 4 event counter input (I) /

CFP15(D5)/P1 function select register(0x402D4)

#DMAEND0

 

 

 

#DMAEND0 output (O)

 

P16/EXCL5/

 

I/O

–

I/O port / 16-bit timer 5 event counter input (I) /

CFP16(D6)/P1 function select register(0x402D4)

#DMAEND1/

 

 

 

#DMAEND1 output (O) / Serial IF Ch.3 data

 

SOUT3

 

 

 

output

 

(I): Input mode, (O): Output mode, (Ex): Extended function

∗ : A 3-V system I/O voltage can only be used for the P10–P14 pins.

B-III-9-4

EPSON

S1C33210 FUNCTION PART