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MSM6546/6546L

¡ Semiconductor

PIN DESCRIPTIONS

Symbol

Type

Description

PORT0

(P0.0 to P0.3)

I/O

4-bit input-output port, I/O switchable, with/without input pull-down resistor

I/O

4-bit input-output port, I/O switchable, with/without input pull-down resistor

I/O

4-bit input-output port, I/O switchable,

with/without input pull-down resistor

I/O

4-bit input-output port, I/O switchable, with/without input pull-down resistor

I/O

4-bit input-output port, I/O switchable, with/without input pull-down resistor

I/O

4-bit input-output port, I/O switchable, with/without input pull-down resistor

I/O

4-bit input-output port, I/O switchable,

with/without input pull-down resistor

4-bit input port

Tie to the negative pole of the battery when

not used.

BD

O

Buzzer output pin

RESET

I

Reset pin with input pull-down resistor

TEST1

Testing pins with input pull-down resistor;

Tie to the negative pole of the battery.

TEST2

I

TEST3

XT

I

Connection pins for crystal oscillator

XTB

O

—

0 V power supply pin

—

–1.5 V supply pin (power supply pin for –1.5 V operation)

—

–3.0 V supply pin (power supply pin for –3.0 V operation)

—

Connection pins for internal potential development capacitor

PORT1

(P1.1 to P1.3)

PORT2

(P2.0 to P2.3)

PORT3

(P3.0 to P3.3)

PORT4

(P4.0 to P4.3)

PORT5

(P5.0 to P5.3)

PORT6

(P6.0 to P6.3)

P2.0 to P2.3

External interrupt

port

P6.3: SCLK

Shared with serial

port

I

PORT7

(P7.0 to P7.3)

P7.0: SOUT

P7.1: SIN

P7.2: BU/D

Shared with 4-bit

up/down counter

P7.3: CCLK

—

Supply pin for internal logic (constant voltage circuit output pin)

—

–4.5 V supply pin

SEG0 to SEG53

O

LCD driver