Chapter 13

DECwriter Corres­pondent (LA12)

Overview

Digital’s DECwriter Correspondent is a plain-paper, dot-matrix teleprinter with the communications power and the reliability that you need to reach the system and get your job done.

The lightweight Correspondent, not much larger than an attaché case, is portable. It combines the printing and forms-handling capabilities of a tabletop terminal with the communications and versatility of a portable teleprinter.

The Correspondent brings your computing power to any of a variety of applications like remote order processing, database information retrieval, and program development.

There are three DECwriter Correspondent models to choose from:

• LA12-AB – Designed for the greatest flexibility, this model includes a 300-baud acoustic coupler, an integral 300/1,200-baud modem that allows the terminal to originate or answer calls to the host, and direct coupling via a telephone connector. This model can switch between the integral modem and the acoustic coupler by means of a simple set-up command on the keyboard. The modem in this model lets you dial through the keyboard and even stores telephone numbers.
• LA12-CB – Includes all the features of the LA12-AB except the 300/1,200-baud integral modem. Instead, the LA12-CB offers the 300-baud acoustic coupler, which provides the user with a cost-effective means of portable communication.
• LA12-DB – Designed to provide the most cost-effective tabletop solution to the user’s system console needs. The LA12-DB provides the same functionality and teleprinter capabilities as the LA12-AB, without the integral modem or the acoustic coupler. This model is designed to interface directly to a system by using an EIA-RS-232C-compatible connection, which is standard on all models.

Major Features

The DECwriter Correspondent’s main features are:

• Built-in communications options – Some models come with modems and acoustic coupler already installed, other models allow you to add these features as you need them.
• Impact printing – Designed for use with plain paper, and multipart forms. Plain paper is less expensive and more convenient than the thermal paper that other portable teleprinters use.
• Smart bidirectional 150 char/s printing – Allows for fast throughput, and reduces computer connection time and telephone costs.
• Variety of character sets – Choose from U.S. ASCII, multinational, and APL character sets to meet your application needs.
• Small, portable terminal with carrying case – Lets you carry it to where the work is. The small size enables you to fit the Correspondent on a desk or under an airline seat.
• Conversational keyboard set-up – Easy to use and simple to change set-up features.
• Graphics printing – Allows the integration of charts, diagrams, and graphs anywhere you work.

Printing Features

Print Modes

The DECwriter Correspondent offers program-selectable text and graphics modes.

Draft Printing

The nine-wire dot-matrix printhead provides high-speed output at the rate of 150 characters per second. By using a nine-wire printhead, the LA12 prints below-the-line descenders, such as in the letters “p”, “q”, and “y”, as well as underlining in all text modes. The Correspondent prints using a bidirectional technique, in which the printhead seeks the shortest distance to the next printable character and skips rapidly over blank spaces. This method reduces computer connection time and telephone connection time, thus reducing costs.

Graphics Printing

Bit map graphics mode allows for the creation of an infinite variety of pictures and graphs, including bar charts, logos, signatures, and unique characters. Graphics can be integrated with text or data to emphasize points. While the DECwriter Correspondent provides a horizontal resolution of 72 dots per inch, it also lets you select any one of eight vertical resolutions. Check the DECwriter Correspondent Programmer Reference Manual for more details.

A predetermined escape sequence from the host enables the LA12 to enter the bit-map graphics mode. Microcode control of individual printhead wires makes every dot addressable by the host and enables images to be displayed on a video terminal to be faithfully reproduced.

Character Modes

The DECwriter Correspondent has the following operator-selectable character sets resident at all times:

• Full 128-character ASCII uppercase/lowercase (94 printable characters)
• 10 national character sets – United States, British, Finnish, French, French Canadian, German, Italian, Norwegian/Danish, Spanish, and Swedish
• APL, VT100 line-drawing, and graphics representation of control characters

The DECwriter Correspondent can print double-width, compressed, or bold characters via selectable software. Character size can be changed from 10 to 12 characters per inch (pica to elite). In addition, the compressed print displays a full 132 columns for spreadsheet work on standard 21.6 centimeters (8.5 inches)-wide page.

Paper

The versatile DECwriter Correspondent can print on single sheets ranging from 7.7 to 21.6 centimeters (3 to 8.5 inches) wide. In addition, roll paper to a maximum width of 21.6 centimeters (8.5 inches) wide can be used, as well as fanfold paper 24.1 centimeters (9.5 inches) wide. It will print on two-part forms where the bond weight ranges between 10 and 20 pounds.

Options

Accessories and Supplies

The following accessories, supplies and spares are available for the DECwriter Correspondent Printing Terminal (LA12). Check with your sales representative or Digital’s Installed-Base Group for the latest information.

Accessories

Supplies

Spares Kits

Operator Features

The DECwriter Correspondent (LA12) has five different categories of controls and indicators that you use to operate and monitor the terminal. They are terminal controls, the keyboard, visual and audible indicators, and the set-up modes.

Terminal Controls

Voltage Selector Switch

This switch changes the terminal to match the available AC input voltage range. Note: Failure to set the voltage selector switch to the correct voltage range may damage the power supply. The default setting for 120 Vac, 60 Hz.

Power ON/OFF Switch

This switch turns power to the terminal on or off. The on position is labeled “1”, and the off position is labeled “0”.

Paper Release Lever

This lever is used to reposition or remove friction feed paper from the terminal.

Bail Bar Lever

The bail bar lever is used to hold paper securely against the platen during printing.

Printhead Adjustment Lever

The space between the printhead and the platen is controlled by this lever. It enables adjustment of the printhead for clear printing on single or multipart forms.

Ribbon Adjustment Knob

The ribbon adjustment knob is used to tighten the ribbon when installing a new ribbon cartridge.

Keyboard

The DECwriter Correspondent’s keyboard is arranged like a standard office typewriter and operates in a similar manner. It includes a numeric keypad for rapid entry of numeric data. The keys are grouped into four categories: standard keys, function keys, set-up keys, numeric keypad keys.

Standard Keys

The standard keys are standard typewriter keys and include CAPS LOCK and SHIFT. In local mode or when local echo is selected, they operate the same as typewriter keys.

Auto repeat allows for a key that is depressed for more than half a second to sends its code to the computer repeatedly until the key is released. Normally, you would just press the desired key and release it, sending the desired character to the host computer once. All keys will auto repeat except for SETUP, VIEW/RESET, ESC, NUM KEY MODE, HERE IS, LOC FF, BREAK, RETURN, and any key pressed with CTRL.

The CAPS LOCK is a two-position locking key, similar to the LOCK key on a standard typewriter. When it is in the down position, only the alphabetic keys generate uppercase characters, regardless of SHIFT key position. When it is in the up position, the alphabetic keys generate lowercase characters. The numeric, special symbol, function, and numeric keypad keys are not affected by the CAPS LOCK key in either position.

Both of the SHIFT keys cause all standard keys on the keyboard to generate uppercase characters. The SHIFT keys do not affect the function keys or the numeric keypad keys.

Function Keys

The DECwriter Correspondent features over 17 function keys. Some of these keys and their functions are:

• DATA TALK – Establishes terminal-to-computer communications through the integral direct-connect modem.
• ESC – Causes the terminal to generate the escape control character.
• CTRL – Causes the terminal to generate control characters when certain control keys on the keyboard are pressed while holding the CTRL key down.
• LINE/LOCAL – Switches the terminal between on-line mode and local mode. When the terminal is on-line, the LINE indicator is lit.
• HERE IS – Sends the answerback message to the host, if the terminal is on-line and an answerback message has been defined and stored.
• BREAK – Causes the terminal to transmit a short break signal with a fixed time duration.
• BELL G – When pressed at the same time as the CTRL key, this key generates a bell control character. It sounds the bell tone when in local mode or when local echo has been selected.
• NUM KEY MODE – Used to switch operation of the keyboard from normal mode to numeric keypad mode. In normal mode, the numeric keypad keys function as standard keys. In numeric keypad mode, these keys are used as calculator keys and the standard keys are disabled.

Numeric Keypad Keys

These are built into the standard keyboard for use in performing calculator type operations. This function is enabled through the use of the NUM KEY MODE key described earlier. The KEYPAD indicator is on when the numeric keypad mode has been selected. The numeric keypad cannot be activated if the terminal is in SET-UP mode.

Set-Up Keys

The Set-up keys allow you to tailor your terminal’s operation to your needs. The SET-UP key itself lets you enter and exit from Set-Up mode.

The Set-Up keys allow you to:

• Set or clear tabs.
• Set the top, bottom, left, or right margins.
• Set or clear margins.
• Select the current paper position as the top of the form.
• Position the paper and set page length.
• Print the terminal status message. This status message tells you what Set-Up features have been selected.
• Recall the Set-Up features stored in the nonvolatile memory.
• Store the operator-selected features in the nonvolatile memory.

For more information on how to set up your terminal, refer to the DECwriter Correspondent Operator Guide or to the set-up mode section of this chapter.

Visual Indicators

When power is applied to the terminal, the visual indicators are on for about six tenths of a second to allow you to check for a bad indicator.

Audible Indicators

There are two audible indicators in the terminal. A keyclick sound occurs when any key is pressed, if the keyclick feature was selected in set-up. A bell tone, on the other hand, will sound under any of the following conditions:

• Input buffer overflow – occurs when the terminal cannot process characters from the input buffer before the buffer fills.
• Keyboard buffer overflow – caused by typing faster than the terminal can transmit characters from the keyboard buffer.
• Bell code – each bell code received by the terminal sounds the bell tone.
• Printhead jam – causes the Power/Fault indicator to flash as well as the bell tone to sound.
• Incorrect entry of the answerback message – caused by attempting to type more than 30 characters for the answerback message.

The corrective action to take for any of these situations can be found in detail in the DECwriter Correspondent Operator Guide.

Set-Up Features

When selecting a set-up feature, you can choose between using the set-up key and the corresponding function key or typing the appropriate sequence. This section contains brief descriptions of some of the operator-selectable features of the DECwriter Correspondent. These set-up features enable you to prepare the terminal for specific applications. If you require additional information, consult the DECwriter Correspondent Operator Guide or the DECwriter Correspondent Programmer Reference Manual.

The operator-selectable features can only be changed while the terminal is in SET-UP. The suggested sequence to change or select set-up features is:

1. Enter Set-Up by depressing the CTRL and SET-UP keys simultaneously.
2. Print a status message to check feature settings.
3. Change one or more of the features, such as tabs, baud rate, or character set to the desired setting.
4. Store the features, if desired, in the nonvolatile memory. The terminal will remember the stored features even if the power is turned off.
5. Print a second status message to check that all features are correct.
6. Exit Set-Up by depressing the SET-UP key.

Set-Up can be entered while in On-Line or Local mode. To prevent the loss of data, take care to enter Set-Up only when the host is not transmitting characters.

    COMMUNICATIONS

    Auto-Ansbk=no
    Buffer=1024
    Comm port=EIA
    Disc-HDX=none
    Echo-local=no
    Fault=xoff(DC3)
    G-HDX= start mode=Rcv
    H-Hi Speed(bps)=1200
    L=Lo Speed(bps)=300
    M-line prot=FDX-data leads
    O-Rcv error ovride=no
    Parity=7/M
    Q-SRTS polarity=Lo
    Restraint=xon/xof
    S-Speed select=Lo
    Turn char=none
    U-power up=line
    V-Frequency=Bell 103

    KEYBOARD

    Auto-linefeed=no
    Break=yes
    C-Keyclick=yes
    Keypad=normal
    Language=USA
    Repeat=yes

    PRINTER

    A-G0 char set=USA
    B-G1 char set=USA
    C-G2 char set=USA
    D-G3 char set=USA
    End-of-line=wrap
    Form Length=264
    G-Print ctrl chars=no
    Horiz pitch (cpi)=no
    NewLine char.=none
    Print Force=hi
    Vert pitch (lpi)=6

    VERSION

    V=V1.2

Communications Features

In order for the terminal to transmit and receive data, the terminal must be compatible with the computer and the communication system. The communication feature selections provide you with the means for matching the terminal and the system.

Some of the communication features available are:

Auto-Answerback

This is actually a response by the terminal to a message sent from the host, so that the terminal can be used unattended. It controls automatic transmission of the answerback message when a communication connection is made. Your choices are on or off.

Buffer

You can set the buffer size to either 256 or 1,024 characters.

Communications Port

Selects the communications port to be used between the terminal and the computer.

Standard choices vary according to the model you have, and include EIA interface, 300/1,200 b/s Direct Connect Modem (DCM) with keyboard dialing, and 300 b/s Acoustic Coupler Modem (ACM).

Optional choices include 20 mA interface and 300/1,200 b/s Direct Connect Modem (DCM) with keyboard dialing.

Local Echo

When the local echo feature is chosen, every character sent to the computer is also printed by the terminal. If local echo is off, then characters transmitted to the computer are not printed by the terminal.

Fault Action Feature

This selects the action the terminal takes when a fault occurs. Selection of terminal action depends upon the system it is being used with. Three physical faults can be detected and acted upon.

When the cover is open, the Power/Fault light flashes, and printing stops. If the printer is out of paper, the Power/Fault light flashes, and vertical paper motion stops. When the fault is a printhead jam, the Power/Fault light flashes, and any printing stops.

You can choose one of the following choices at any time: no action, send XOFF, short break, or perform disconnect.

Half-Duplex (HDX) Initial Direction

When the terminal initiates communication with a computer, the HDX initial calling direction is checked. This direction determines if the terminal starts in the receive or transmit data state. This feature functions only when the EIA port is selected for communication. Consult your DECwriter Correspondent Operator Guide for information on using European modems.

Baud Rate Operating Range Selection

Lets you select either the high-speed or low-speed baud rate operating range. Individual speeds or split speeds can be selected within each range. In some system, transmit and receive speeds are different. The speed selection feature allows you to adapt your terminal to all compatible systems. Note: See the DECwriter Correspondent Operator Guide for more details.

Before choosing an individual baud rate speed, first select high-speed range, low-speed range, or modem selection.

Individual Baud Rate Speed Selection

Once you have selected the high-speed or low-speed range, you can now select individual speeds or split speeds in bits per second.

Individual speeds include 50, 75, 110, 134.5, 150, 200, 300, 600, 1,200, 1,800, 2,400, 4,800, 7,200, and 9,600 bits per second.

The split-speed choices are 75 send/600 receive, 75 send/1,200 receive, 150 send/600 receive, 150 send/1,200 receive, 300 send/2,400 receive, 300 send/4,800 receive, 600 send/2,400 receive, and 600 send/4,800 receive.

Modem Protocol

Modem protocol selection lets you match your system’s communication protocol. You can choose from:

• Full-duplex (data lead only)
• Full-duplex (full control)
• Half-duplex (supervisory/EIA only)
• Half-duplex (coded without reverse channel/EIA only).

Error Override

Allows the parity bit of all received characters to either be checked or ignored. This is valuable when the received parity bit is not the same as the transmitted parity bit or when there is no received parity bit.

Parity

Selects data bits per character and parity. The data bits per character can be set to 7 or 8 data bits. Parity selects the type of parity bit that the terminal generates for transmitted characters and checks for the received character.

Choices include: no parity, 7 data bits with eighth bit set to mark; no parity, 7 data bits with eighth bit set to space; even parity, 7 data bits; odd parity, 7 data bits; even parity, 8 data bits; odd parity, 8 data bits; and no parity, 8 data bits.

Restraint Control

Provides a signal to the computer that is should temporarily suspend data transmission to prevent an overflow in the input buffer. With the DECwriter Correspondent you can choose from among no restraint control, XOFF/XON for restraint control, secondary request to send (SRTS) line for restraint control, and both XOFF/XON and SRTS line for restraint control.

Half-Duplex Turnaround Character

Selects the control character that will be used to turn the line around from being controlled by the computer to being controlled by the terminal, or vice-versa. When the character is received, the terminal controls the communications lines, and when the character is transmitted, the computer controls the lines.

Modem Frequency Selection

Allows modem operation to be compatible with both U.S. and European communication requirements.

Keyboard Features

Some features are available to adapt the keyboard to various terminal applications. These include:

Printer Features

Printer features allow you to position a form, set or clear margins and tabs, and select vertical and horizontal pitch. These features can be easily selected through the keyboard by typing in the appropriate escape sequence.

You can select:

Character Sets

The DECwriter Correspondent has the capability of printing only one character set, 94 characters, at a time. In order to allow for a larger selection of printable characters, the characters that can be printed by the terminal are divided into 11 sets – U.S. ASCII, U.K., French Canada, Germany, Sweden, Finland, Norway/Denmark, Italy, Spain, APL, and VT100 Line Drawing. Any of these sets can be selected as the first (G0), second (G1), third (G2), or fourth (G3) printing character set. The computer uses ANSI escape sequences to select the desired set. In order to select a particular character set, you just select one of the following escape sequences.

End-of-Line Handling

As your text approaches the right hand margin, you can elect to have the line wrap around to the next line or truncate.

Page Length

At power-up, the form length is set to 27.9 centimeters (11 inches), corresponding to 66 lines with the default vertical spacing.

The form length command allows you to set the number of lines per page. This is accomplished by using a simple equation to calculate the page length, P_n.

P_n(lines/page) = desired page length (inches/page) × current vertical pitch (lines/inches)

The following chart gives you an idea of some of the more common settings.

The page length can be set to any length from 1/12 inch per page to 21 inches per page at the selected vertical pitch. If the desired page length exceeds 21 inches, then the printer will default to 21 inches.

XON/XOFF Control Characters

You can use the restraint control feature – XON/XOFF to prevent input buffer overflows. When the input buffer receives more characters than a specified upper limit (800 characters), the terminal transmits the selected signal, XOFF, to the host. The host then stops transmitting characters.

As the terminal continues to remove and print characters, the number of characters in the buffer decreases. When the input buffer holds 10 characters, the terminal transmits a second signal, XON, to the host, who then resumes transmission.

Horizontal Pitch

This allows you to vary the width of printed characters as well as their spacing (number of characters per inch). You can choose to print 10, 12, 13.2 or 16.5 single-width characters per inch. If you wish to print double-width characters, you can vary the pitch by 5, 6, 6.6, or 8.25 characters per inch.

The horizontal pitch selected determines the maximum column width as per the chart below.

Horizontal Margins

The horizontal-margins sequence sets the left and right margin. If both parameters are not zero, and the first parameter is smaller than the second on, then the left margin will be set to the first parameter, while the right margin will be set to the second parameter. Note: Changing the horizontal pitch modifies the horizontal margins.

Horizontal Tabs

A horizontal tab is a preselected point on a line to which the printhead advances when a horizontal tab control character is received. The DECwriter Correspondent has 132 possible horizontal tabs stops, one for each column. These tab stops are associated with column numbers, not physical positions on the paper. Thus, as was the case with horizontal margins, changing horizontal pitch will also change the physical position of tab stops.

Print Resolution

With the DECwriter Correspondent, you can select either normal printing, or for greater emphasis, bold printing.

Override Paper-Out

For your application, it may be desirable to disable the paper out switch. With the DECwriter Correspondent, you can select this feature.

Normally, when the paper-out switch detects that you are about to run out of paper, it stops printing about one inch from the end of the page. If your application requires printing to the very end of the page, you can use the paper-out override.

Print Force

Selecting the proper print force for your application is another feature provided by the DECwriter Correspondent. Multipart forms require a high print force. This ensures that each copy is as clear and legible as the first. A low print force is better for single copies. By using the low force, your printhead lasts longer, and printing is quieter.

Vertical Pitch

This allows you to vary the number of lines per inch. You can select to use 2, 3, 4, 6, 8, or 12 lines per inch.

Vertical Margins

You can set top and bottom vertical margins with this feature. The top vertical margin specifies the first printable lines, while the bottom vertical margin specifies the last printable line. When vertical pitch and form length are changed, the vertical margins must be reset.

Vertical Tabs

A vertical tab is a preselected line to which the printhead advances when a vertical tab control character is received. The printer has 168 vertical tab positions. Vertical tabs can be set and cleared like horizontal tabs. Vertical tab stops are associated with specific line numbers, not physical positions on the paper. Thus, changing vertical pitch changes the printing position of the vertical tabs on the paper.

Memories

The DECwriter Correspondent terminal features are contained in three memories – operating, user permanent, and default.

The terminal operates according to the features entered in the operating memory. You can change a feature in the memory by entering SET-UP and changing the feature. The operating memory features are horizontal and vertical pitch, margins, and tabs, form length, and printer character sets.

User permanent memory is used to store operator selected features. The computer cannot change the features stored in this memory. You can change them by entering SET-UP, changing the feature, and performing a store procedure. User memory features can be loaded into operating memory by performing a recall procedure. When a recall procedure is performed, all the features previously stored in operating memory are erased.

Default memory contains the typical selections for each SET-UP feature. These are stored in the permanent memory and cannot be changed by the operator.

Escape Sequences

The DECwriter Correspondent (LA12) uses escape sequences standardized by the American National Standard Institute (ANSI) to control many of its features. These escape sequences provide additional controls that are not provided by the control characters in the character set. These sequences are multiple-character control functions are not printed, but are used to control printing and processing of characters.

Detailed information on escape sequences can be found in the DECwriter Correspondent Programmer Reference Manual or in Appendix H at the end of this book.

Maintenance

The DECwriter Correspondent requires no preventative maintenance other than surface cleaning. You can clean the external surfaces and platen with a damp cloth. Do not use excessive water or cleaners with solvents. Rubbing the keycaps with a dry or barely moist cloth is enough to clean them. Note: Do not remove the keycaps for cleaning; damage to the switch contacts can occur if the keycaps are not replaced correctly.

The terminal covers are not meant to be weatherproof. There are several openings in the covers through which liquids, coins, paper clips, and other objects can fall. Metal objects will disturb the electronic operations of any terminal if they come within contact of the circuitry. For this reason, it is recommended that you do not place drinks or metal objects on any part of the terminal.

The ventilation slots on the top and bottom of the terminal should be kept clear to prevent overheating.

Self-tests

The DECwriter Correspondent offers a selection of self-tests. A power-up and printer self-test occur automatically when the terminal is turned on. These provide an initial visual indication of terminal operation. The other tests can be keyboard-operated for further testing of terminal operation from set-up mode.

Other tests include:

• EIA Operation Self-tests
  1. Analog loopbacks – tests internal circuits and data input/output lines
  2. Baud rate/line signal – tests EIA communication signals and data transmission at all baud rates.
• Integral Modem (DCM) Self-tests
  1. Analog loopback – internal test only. Does not test communication lines.
  2. Remote data loopback – tests internal circuits and communication lines between the terminal and the remote modem.
• Acoustic Coupled Modem (ACM)/Analog Loopback – internal test only. Does not test communication lines.

The Correspondent also features a Self-test Help Message that shows the necessary keystrokes for any of the terminal self-tests. To see this message, enter set-up mode, type “T” and press RETURN. This will enable you to initiate a self-test procedure.

Operator Troubleshooting Checklist

If your printer is not operating, chances are the problem is minor and you can correct it yourself. Listed below are some of the common problems, their probable cause, and the corrective action that you can take. Note: Always turn off the printer before you attempt to correct a problem.

No response when power switch is turned on (set to 1). LED indicators are off. Carriage does not move.

• Power cord not plugged in. – Plug in power cord.
• Fuse burned out. – Replace fuse.
• No power at wall receptacle. – Try another receptacle. Check circuit breaker. Call electrician if necessary.
• Voltage selector switch set at wrong voltage. – Check switch for proper setting.

Power/Fault light flashes. (No bell tone sounds.)

• Printer out of paper. – Install paper. Press View/Fault reset key.
• Access cover open. – Close cover. Press View/Fault reset key.

Power/Fault light flashes. (Bell tone sounds.)

• Carriage or printhead jam. – Check for smooth movement of carriage. Check clearance between printhead and paper. Readjust print impression. Clear jam and reset fault by pressing the View/Fault reset key. Make sure that the printhead is properly seated.

No printing, carriage moves.

• Printhead adjustment. – Adjust printhead closer to platen.
• Ribbon cartridge. – Check printhead for proper seating.
• Printhead. – Remove printhead and check connector on bottom.

Print is too light.

• Printhead. – Adjust printhead closer to platen.
• Ribbon cartridge. – Replace ribbon cartridge.
• Print pressure set-up features incorrect. – Check set-up feature.

Print density impression drops off.

• Ribbon cartridge. – Replace ribbon cartridge.

Print density randomly varies across the page.

• Ribbon cartridge. – Replace ribbon cartridge.

Prints light-to-dark, or dark-to-light.

• Printhead. – Replace printhead.

Missing dots on any printable character (always in the same row).

• Printhead cable. – Check printhead connector.
• Printhead. – Replace printhead.

Missing dots only on some characters.

• Printhead. – Replace printhead.

Prints incorrect characters.

• Incorrect character set. – Select correct character set in set-up.

No line feeds.

• Paper jam. – Remove paper jam and reload paper.

Improper line feeds (inconsistent vertical motion).
Print line slanted in friction feed.

• Paper path obstructed. – Clear paper path.
• Dirty platen. – Clean platen.

Print line slanted in pin-feed application.

• Paper routing. – Check for proper paper path.
• Paper path obstructed. – Clear paper path.

Any one character does not print.

• Keyboard. – Call service.

Printer prints NVM err during store procedure or recall procedure.

• Defective logic board. – Call for service.

No key codes transmitted (EIA operation). Local operation is normal.

• Line/Local key set to Local. – Select Line mode.
• Set-up features. – Check set-up features.
• Wrong loopback connector used. – Use loopback connector P/N 1215336-01.

Prints double characters.

• Local echo feature on. – Disable local echo set-up feature.

Acoustic coupler test fails.

• Internal failure. – Call for service.

Acoustic coupler test passes but there is no communication.

• Incorrect set-up. – Check communication features.

Direct connect modem test fails in analog loopback mode.

• Internal failure. – Call for service.

Direct connect modem test fails in remote data loopback mode.

• Incorrect set-up feature. – Check set-up features.

Additional Documentation

The following documents contain more detailed information about the DECwriter Correspondent (LA12).

DECwriter Correspondent Operator Guide (EK-CPL12-OP)

Describes the information required for you to operate the terminal.

DECwriter Correspondent Programmer Reference Manual (EK-CPL12-RM)

Includes information on the functions of the terminal that can be controlled by the host and the procedures the programmer can use to implement control of these functions. Programming can be performed locally by using the terminal keyboard if desired.

DECwriter Correspondent Installation Guide

Provides information on such topics as: ribbon cartridge installation, AC line cord connection, roll paper and tractor feed paper loading, printer self-test initiation, and integral modem and acoustic coupler operation.

Also of interest are:

PDP-11 and VAX Systems & Options Catalogs

Provide you with the most accurate and up-to-date information on currently available PDP-11 and VAX systems, options, and software products. These customer documents are designed to help you select the right Digital product for your needs. European versions are also available. If you require information not contained in these documents, contact your local Digital representative.

Specifications

Performance Characteristics

Paper

Communications

Power Requirements

Operating Environments

Physical Characteristics