Pad Description

Pad No.

Pad Name

I/O

Mask

Option

Description

4~7

94, 1~3

PS3~PS0

PM3~PM0

I

Pull-high or

None.

Note 2

Input pins for input only

8

TMCLK

I

Pull-high

or None.

Note 4

Input for TIMER clock

TIMER can be clocked by an external clock or an

internal frequency source.

9

RES

I

¾

Input to reset an internal LSI

Reset is active on logical low level.

17~14

10~13

PA3~PA0

PB3~PB0

I/O

CMOS or

NMOS with

Pull-high or

None.

Note 3

Input/output pins

19, 20

BZ, BZ

O

Note 1

Sound effect outputs

21

VDD

I

¾

Positive power supply

23

22

OSCI

OSCO

I

O

¾

An external resistor between OSCI and OSCO is

needed for internal system clock.

25

24

XIN

XOUT

I

O

¾

32768Hz crystal oscillator for time base, LCD

clock

26

VSS

I

¾

Negative power supply, GND

27~30

VLC1~VLC4

I

¾

LCD system power 1/4 bias generated

31~34

VOUT1~VOUT4

I

¾

LCDsystemvoltageboostercondenserconnecting

terminal

35~50

COM15~COM0

O

¾

Output for LCD panel common plate

51~90

SEG39~SEG0

O

¾

LCD driver outputs for LCD panel segment

93

18

92

91

T512

T1D

TEST1

TEST2

O

O

I

I

For test mode only

TEST1 and TEST2 are left open when the chip is

in normal operation (with an internal pull-high

resistor).

Note: 1. The system clock provides six different sources selectable by mask option to drive the

sound effect clock. If the Holtek sound library is used, only 128K and 64K are acceptable.

2. Each bit of ports PM, PS can be a trigger source of the HALT interrupt, selectable by

mask option.

3. Each bit of ports PA, PB can be selected as CMOS for output pin only, or as NMOS for

I/O pin with pull-high resistor or none by mask option.

4. 14 internal clock sources can be selected by mask option to drive TMCLK. Note that

TMCLK should not be connected to a pull high resistor if an internal source is used.

HTG12B0

5

September 8, 1999