beautypg.com

Communications interface, Parallel interface – TransAct Technologies ITHERM 280 User Manual

Page 32

background image

Specifications and Requirements

iTherm

®

280 Programmer’s Guide

Page 30

Rev C

28-07764

Communications Interface

Parallel Interface

Your printer features two parallel interfaces:

An IEEE 1284-A 25-pin, D-shell connector, with pin-outs that interface to a

standard IBM PC parallel printer interface with a one-to-one cable.

An IEEE 1284-B, which is a standard Centronics 36-pin connector.


Both interface cards provide a dual cash drawer interface. The following table lists
interface signals and corresponding pins.

25-pin Connector

36-pin Connector Signal

Description

Direction

Pin 1

Pin 1

STROBE

Clock data to printer

Host to Printer

Pins 2-9

Pins 2-9

D0 - D7

Data

Host to Printer

Pin 10

Pin 10

ACK\

Printer accepted data

Printer to Host

Pin 11

Pin 11

BUSY

Printer busy

Printer to Host

Pin 12

Pin 12

PE

Paper Out/Status

Printer to Host

Pin 13

Pin 13

SLCT

Printer selected

Printer to Host

Pin 14

Pin 14

AUTOFD

Autofeed paper

Host to Printer

Pin 15

Pin 32

FAULT\

Printer error

Printer to Host

Pin 16

Pin 31

INIT\

Initialize printer

Host to Printer

Pin 17

Pin 36

SLIN

Select printer

Host to Printer

Pin 17

FG

Frame ground

Printer to Host

-

Pin 18

+5V

Peripheral logic high

Printer to Host

Pins 18-25

Pins 16, 19-30

GND

Ground

Table 4 Parallel Interface Pin-outs


Signal Levels

Voltage levels

0 V and +5 V (nominal)

Logic levels

Logic one

Driver

+2.4 V to +5 V

Receiver

+2.0 V to +5 V

Logic zero

Driver

0 V to +0.4 V

Receiver

0 V to +0.8 V


Current requirements

Logic one

Source

0.25 ma at +2.4 V

Logic zero

Sink 16 ma


Line termination

Data and control

3.3k ohm to +5 V

Strobe

1.2k ohm to +5 V