The Interface Boards

A number of optional interfaces are available in case your computer is either not provided with a parallel interface or you wish to increase the memory capacity of your printer’s buffer.

Choosing an Interface

Optional interfaces can be divided into three main categories which are described briefly below.

IEEE-488 interfaces offer standardized connections, trouble-free operation, and the ability to connect computers, printers, and other devices on the same line so that they may share data freely.

The buffered parallel interfaces also offer trouble-free operation and standardized connections. They provide the printer with more memory to free the computer for other tasks when printing large amounts of text or graphics. You can increase the printer’s data buffering capacity by an additional 32 KB (about 10 pages).

Serial interfaces are required if your computer is not equipped with a parallel interface or if you need an interface that conforms to the

Current Loop standard instead of RS-232C. These interfaces also provide some combination of the following features: X-ON/X-OFF data communication protocol, loopback self test modes, and data buffers that increase the printer’s data buffering capacity.

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The Interface Boards

Compatible Interfaces

The following is a list of Epson interfaces that are compatible with your printer.

Interface number

#8143

#8148

#8165

#8172

Name

New Serial Interface

Intelligent serial interface

Intelligent IEEE-488 interface

32 KB buffered parallel interface

All Epson interfaces have the Epson name printed on them. If the board has an identification code printed on it, it is a four-digit number beginning with 8 and should correspond to one of the numbers listed in the table above.

Also, Coax and Twinax interfaces are available from third party vendors. These interfaces allow connectivity to mainframes and minicomputers and emulation of IBM printers. The Coax (EP-Connect) is available from Avatar Corporation (508) 435-6872, and the Twinax

(I-O8300) is available from I-O Corporation (801) 973-6767.

Installation

1. Turn off your printer. Then unplug the printer and disconnect the interface cable.

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The Interface Boards r!!!!!?

WARNING:

High voltages are present inside the printer when the power is on. Do not attempt to remove the upper case unless the printer is turned off and the power cord is unplugged. Also, try not to touch contacts on the circuit board of the printer because many of the components can be destroyed by the static electricity present in your body.

Do not change the settings of any DIP switches on the main board.

2. Remove the paper guide.

3. Remove the screw securing the interface board cover.

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4. Lift off the cover.

The Interface Boards

5. Remove the screw labeled CG from the main board.

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The Interface Boards

Installing the board

There are two basic interface board designs-one with the FG wire not attached and one with the FG wire attached. This slight difference changes the way the boards are installed in the printer but does not affect the operation of the interface in any way. Check to see which type of interface board you have.

FG wire not attached

See next page

FG wire attached

Skip to page 5-47

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The Interface Boards

FG wire not attached

1. Use the CG screw to attach the round end of the FG (frame ground) wire to the main board and position the other end as shown.

2. Carefully insert the pins on the optional interface board into the mating connector on the main board; then secure the board with the screws provided.

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The Interface Boards

3. Attach the plug end of the FG wire onto the FG pin located on top of the interface board.

4. Set the DIP switches on the interface board according to the manual accompanying it.

FG wire attached

1. Carefully place the interface board next to the printer as shown below. Use the CG screw to connect the round end of the FG

(frame ground) wire to the main board.

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The Interface Boards

2. Holding the interface board level, rotate it into position and attach it to the main board. Make sure that the connector pins are properly inserted into the mating connector.

3. Secure the board with the screws provided.

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The Interface Boards

4.

For all interface boards except #8143 New Serial Interface board, set the DIP switches on the interface board according to the manual accompanying it. If you have the #8143, see page 5-50.

Attaching the interface board cover

1. Bend back the hinge plate on the interface board cover as shown below.

Note: When you reattach the interface board, rebend the plate to cover the opening. The plate is sturdy, but be careful not to subject it to excessive bending.

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2. Reattach the board cover.

The Interface Boards

CAUTION: When an optional interface board is installed, be sure to disconnect the printer cable from the printer’s built-in

#8143 New Serial Interface

If you are using an optional interface, it may be necessary for you to alter the communication protocol of the printer or the computer so that they can communicate properly. In most cases, you should use the information in your optional interface manual or your computer’s manual to match the computer with the interface.

If you are using the #8143 optional interface board, make sure that you read through the section below on baud rate selection. You may also want to see the following sections on handshaking timing and error handling for interface information specific to your printer.

For all other data transfer conventions, such as word structure or communications protocol, use the information in the manual supplied with your #8143 optional interface.

Using

the

Printer Options 5-49

The Interface Boards

Baud rate selection

You can select baud rates from 75 to 19,200 BPS (Bits Per Second).

When setting the baud rate, make sure you use the bit rate selection table for printers with buffers (in the #8143 interface manual).

For more information on the printer’s input buffer settings, see the section on DIP switch functions in Chapter 3 of this manual.

Handshaking timing

When the vacant area for data in the input buffer drops to 256 bytes, the printer outputs an X-OFF code or sets the DTR flag to "1" (MARK) indicating that it cannot receive data.

Error handling

When a parity error is detected, your printer prints an asterisk (*). All other errors, including framing and overrun, are ignored.

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Chapter

6

Maintenance

Cleaning the Printer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2

Replacing the Ribbon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5

Transporting the Printer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-11

Maintenance 6-1