EPL-6000 LASER PRINTER

Interface timing

The figure below shows the timing for the parallel interface.

SELECT -A

DATA’-a 4

DATA STROBE

‘“i.Tke

BUSY

ACK

A: 1 ps (min.) 8: 1 )B (min.) C: 1 ps (min.) D: approx. 6 ps

Signal levels

Output signals:Vo,=Oto0.4V v,, = 2.4 to 5.0 V

Input signals:

v,, =0 to 0.8 V

 

V,” = 2.0 to 5.0 V

Serial interface

The laser printers built-in serial interface can be set for either RS-232C or RS-422A operation. These interfaces have the following characteristics.

Data format

 

 

Word length:

7 or 8 bits

Parity:

0 or 1 bit (None, Odd, Even, Ignore)

Start

bits:

1

bit

Stop

bits:

1

or 2 bits

The data format can be set using functions and menu items in SelecType.

Baud rate

300, 600, 1200, 2400, 4800, 9600, 19200 bits per second.

Signal level

 

RS-232C:

v, = 2.2 to 12 V

 

v, =-I.4 to -12V

RS-422A:

v, = 2.5 to 5V

 

v, = 0 to 0.5 V

Transmission procedures

Ready/ Busy:

•The DTR signal level changes to HIGH when the printer is ready to receive data (or to LOW if set for inverted operation by SelecType).

•The DTR signal level changes to LOW when the printer is not ready to receive data (or to HIGH if set for inverted operation by SelecType).

XON/XOFF:

•When the printer is ready to receive data, it sends an XON (11 hex) to the host computer through the TD line for the RS-232C interface or SD+ and SD- lines for the RS-422A interface. When ROBUST-XON is set to ON (by SelecType). and data is not received within one second of the XON signal being sent, the printer sends an XON signal every second. If ROBUST- XON is set to OFF, the printer sends only one XON signal.

•When the printer is not ready to receive data, it sends an XOFF (13 hex) to the host computer through the TD line for the RS232C interface or SD+ and SD- lines for the RS-422A interface.

•The printer is ready to receive data when it is on line, no error conditions exist, and the buffer is not tilled above the overload value set with SelecType.

•The printer is not ready to receive data when it is off line or when it is on line but the remaining capacity of the data buffer is less than the overload buffer value.

Serial interface pin assignments

The serial interface connector pm assignments and a description of the interface signals are shown in the table below. The direction of signals is given relative to the printer.

 

 

I

 

 

Description

 

 

 

 

 

 

 

Frame ground. Safety

I

 

ground Iine.

 

 

 

 

 

 

 

Transmit data

 

 

 

This pin transmits serial

 

 

 

data from the printer to

 

 

 

the computer.

I

 

Receive data.

 

 

 

This pin transmits serial

 

 

 

data from me computer to

 

 

 

 

 

 

 

Request to send. This pin

 

 

 

is HIGH when power is on

 

 

 

Clear to send. This pin

 

 

indicates that the computer

is ready to receive data

from the printer.

Data set ready. This pin indicates mat the computer is ready to communicate

Signal ground. This pin -1provides a ground for all the signal lines.

Send data. This

pin sends serial data from

the printer to the computer. ,

Signal level is RS-422A

/

 

Send data. This

 

 

pin sends serial

 

 

data from me printer to

 

 

the computer. Signal level

 

 

is RS-422A

 

 

 

 

 

Same as DTR.

 

I

Receive data. This pin

j

transmits serial data from

the computer to the printer

 

 

Signal Ievel is RS-422A.

 

 

Data terminal ready. This

pin indicates whether or not i

the printer is ready to

;

receive data. If the printer

I

ready protocol is not

/

 

selected, this pin is always ,

HIGH (i.e. the printer is

1

ready to receive data). If

 

printer ready protocol is

 

selected, the printer can

/

accept data when the pin

 

level is HIGH. and cannot

 

accept data when the pin

:

level is LOW. When busy

i

Not a signal, but a +5V

1

power supply output.

i

Maximum of 300mA

/

Laser Printers

7/18/89

EPL-3