ST3020

Preliminary Ver 0.1

Page 4/13

2007/06/20

3

SIGNAL DESCRIPTIONS

Table 3-1 Signal Function Description

Function

Group

Pin Name

Pin #

I/O

Description

RESET

1

I

System reset, low active

PWD

1

I

Power down, low active

PWDA

1

O

Power down acknowledge, high active

OSCXI

1

I

Crystal input or R-oscillator input. If not used, it connects to

GND

OSXO

1

O

Crystal output. If not used, it connects to GND

ECLK

1

I

External clock input. If not used, it connects to GND

CMODE[1:0]

2

I

Clock source select

01=Crystal. ECLK connects to GND

1X=ECLK. OSCXI and OSXO connect to GND

System control

TEST[2:0]

3

I

Test mode. TEST[2:0] connect to GND

SO[1:0]/

DPA[7,15]

2

O

SO0/DPA[7], SO1/DPA[15]

Special I/O

CLKO/

DPA[6]

1

O

Clock output/DPA[6]

GPIO

DAP[13,14],

DPB[0:15]

18

I/O

General I/O

External

Interrupt

XREQ/DPA[5]

1

I

External interrupt/DPA[5]

TF0/DPA[0]

1

O

Transmit frame synchronization/DPA[0]

RF0/DPA[1]

1

I

Receive frame synchronization/DPA[1]

TX0/DPA[2]

1

O

Serial data transmit/DPA[2]

RX0/DPA[3]

1

I

Serial data receive/DPA[3]

Serial Port0/

DPA[4:0]

SCLK0/DPA[4]

1

O

Serial clock/DPA[4]

TF1/DPA[8]

1

O

Transmit frame synchronization/DPA[8]

RF1/DPA[9]

1

I

Receive frame synchronization/DPA[9]

TX1/DPA[10]

1

O

Serial data transmit/DPA[10]

RX1/DPA[11]

1

I

Serial data receive/DPA[11]

Serial Port1/

DPA[12:8]

SCLK1/DPA[12]

1

O

Serial clock/DPA[12]

D[0]/SCL

1

I/O

Parallel : Data bus

D[1]/SDI

1

I/O

Parallel : Data bus

D[2]/SDO

1

I/O

Parallel : Data bus

D[3:7]

5

I/O

Parallel : Data bus

WR

1

I

Parallel : Write enable, low active

RD

1

I

Parallel : Read enable, low active

CS

1

I

Parallel : Chip select, low active

CMD

1

I

Parallel : Command/data select

“H”: Data

“L”: Command

REQ

1

O

DSP wants to sent command to MCU, low active

RDY

1

O

DSP permit MCU access data, low active, not used

MCU Interface

PMODE

1

I

Parallel interface select

0: Parallel (default). Connecting to GND

1: Not used