Continued from preceding page.

No. 5157-11/16

LC72336, 72338

Continued on next page.

Pin No.

Symbol

I/O

I/O type

Function

39

38

37

36

S17/PE0

S18/PE1/SCK2

S19/PE2/SO2

S20/PE3/SI2

I/O

CMOS 3-value

output and

push-pull

Shared-function LCD driver segment output, general-purpose I/O, and serial I/O port

The IOS instruction is used to switch between the LCD driver segment output, general-

purpose I/O, and serial I/O functions, and to switch between input and output for the

general-purpose input port function.

• When used for segment output:

The function can be specified in bit units.

Segment output is specified with the IOS instruction (Pn = 0DH).

b0 = S17/PE0

0 ... Segment output

b1 = S18/PE1

1 ... PE0 to PE3 output

b2 = S19/PE2

b3 = S20/PE3

• When used as a general-purpose I/O port:

Input or output can be specified in bit units (1-bit I/O).

The general-purpose I/O port function is specified with the IOS instruction (Pn = 0).

b2 = SI/O2

0 ... General-purpose port

1 ... SI/O port

Input or output is specified with the IOS instruction in bit units.

PE ... Pn = 4

0 ... Input

1 ... Output

• When used as a serial I/O port:

The serial I/O port function is specified with the IOS instruction (Pn = 0).

The contents of the serial I/O data buffer can be saved and loaded with the INR and

OUTR instructions.

Note: Pin setup states when used as a serial I/O port:

PE0 ... General-purpose I/O

PE1 ... SCK2 output in internal clock mode

SCK2 input in external clock mode

PE2 ... SO2 output

PE3 ... SI2 input

In clock stop mode, if this port is used as a general-purpose I/O port or as a serial I/O

port, the pins go to the input disabled high-impedance state. If used for segment output,

the pins are fixed at the low level.

The segment output port function is selected after a power-on reset.