ST16C452CJ68 Ver la hoja de datos (PDF) - Exar Corporation

Número de pieza

componentes Descripción

Lista de partido

ST16C452CJ68

DUAL UART WITH PARALLEL PRINTER PORT

Exar Corporation 

ST16C452/452PS

SYMBOL DESCRIPTION

Symbol

A0

A1

A2

-ACK

-AutoFDXT

BIDEN

BUSY

CLK

-CSA

-CSB

-CSP

D0-D7

Rev. 3.20

Pin

Signal Type

Pin Description

35

34

33

68

56

1

66

4

32

3

38

14-21

I

Address-0 Select Bit - Internal registers address selection.

I

Address-1 Select Bit - Internal registers address selection.

I

Address-2 Select Bit - Internal registers address selection.

I

Acknowledge (with internal pull-up) - General purpose input

or line printer acknowledge (active low). a logic 0 from the

printer, indicates successful data transfer to the print buffer.

I/O

General purpose I/O (open drain, with internal pull-up) or

automatic line feed (open drain input with internal pull-up).

When this signal is low the printer should automatically line

feed after each line is printed.

I

Bi-Direction Enable - PD7-PD0 direction select. A logic 0

sets the parallel port for I/O Select Register Control. A logic

1 sets the parallel port for Control Register Bit-5 Control.

I

Busy (with internal pull-up) - General purpose input or line

printer busy (active high). can be used as an output from the

printer to indicate printer is not ready to accept data.

I

Clock Input. - An external clock must be connected to this

pin to clock the baud rate generator and internal circuitry

(see Programmable Baud Rate Generator).

I

Chip Select A - A logic 0 at this pin enables the serial

channel-A UART registers for CPU data transfers.

I

Chip Select B - A logic 0 at this pin enables the serial

channel-B UART registers for CPU data transfers.

I

Printer Port Chip Select - (active low). A logic 0 at this pin

enables the parallel printer port registers and/or PD7-PD0

for external CPU data transfers.

I/O

Data Bus (Bi-directional) - These pins are the eight bit, three

state data bus for transferring information to or from the

controlling CPU. D0 is the least significant bit and the first

data bit in a transmit or receive serial data stream.

3

Share Link: