Chapter 17

LXY Family of Graphics Lineprinters

Overview

The versatile LXY12 and LXY22 are medium-duty printing devices that combine the benefits of a dot-matrix printer and a plotter on many of Digital's UNIBUS PDP-11 and VAX systems. When used as lineprinters, the LXY family is compatible with Digital's other lineprinters, need no special software, and are supported by the RT-11, RSX-11, RSTS/E, and VMS operating systems. When used with Digital's PLXY-11 and BCP graphics software packages, you have full access to all the LXY plotting capabilities. PLXY-11 is currently supported by Digital's RT-11, RSX-11M, RSX-11M-PLUS, RSTS/E, and VME operating systems, while BCP is supported by the RSX-11M and VMS operating systems.

Designed for use during a standard eight-hour shift in scientific, industrial, and commercial marketplaces, the LXY family of graphics lineprinters accommodates complex, intricate designs. In addition, the LXY12 and LXY22 provide hardcopy output of designs formulated on a graphics terminal, combine text and graphics in a single report, and produce simple forms.

Plotting capabilities, made possible with the PLXY-11 graphics software package, include standard line drawings, (for example, graphs, histograms, and charts) along with plots requiring shaded or solid areas (for example, bar graphs). The BCP Barcode/Block Character software is ideally suited to industrial and distributive applications where products must be coded and labeled using preprinted stationery and/or gummed labels.

The freestanding LXY12 and LXY22 systems include a controller if required by the configuration, a cable for connecting the controller to the graphics lineprinters, a pedestal with basket and paper guide, and a choice of two software package – the PLXY-11 graphics software and the BCP barcode package.

The LXY12 produces high-quality output at speeds of up to 300 lines per minute when printing and up to 42.4 centimeters per minute when plotting. The LXY22, a higher-speed device than the LXY12, prints up to 600 lines per minute and plots up to 84.6 centimeters per minute. The PDP-11 and VAX Systems and Options Catalogs contain ordering information for different versions of the LXY family.

The following LXY series models are available.

Model Print Speed UNIBUS Controller Serial RS232 Controller DMF32 Controller
LXY12, 120 Vac, 60 Hz 300 l/min -CA -DA -EA
LXY12, 240 Vac, 50 Hz 300 l/min -CB -DB -EB
LXY22, 120 Vac, 60 Hz 600 l/min -CA -DA -EA
LXY22, 240 Vac, 50 Hz 600 l/min -CB -DB -EB

After selecting the appropriate model graphics lineprinter, choose your software from the chart below.

Operating System Distribution Media PLXY-11 Graphics Package BCP Barcode Package
RT-11 800 b/in magtape QJS91-XD
RT-11 1600 b/in magtape QJS91-XM
RT-11 RL01 QJS91-XQ
RT-11 RK06 QJS91-XT
RT-11 RX01 QJS91-XY
RSX-11M 800 b/in magtape QJS90-XD QJS05-AD
RSX-11M 1600 b/in magtape QJS90-XM QJS05-AM
RSX-11M RL01 QJS90-XQ QJS05-AQ
RSX-11M RK06 QJS90-XT
RSX-11M RX016 QJS90-XY QJS05-AY
RSX-11M-PLUS 800 b/in magtape QJS95-XD
RSX-11M-PLUS 1600 b/in magtape QJS95-XM
RSTS/E 800 b/in magtape QJS92-XD
RSTS/E 1600 b/in magtape QJS92-XM
RSTS/E RL01 QJS92-XQ
RSTS/E RK06 QJS92-XT
VMS (11/730) RX01 QDS01-XG QC640-XG
VMS (11/750) TU58 QDS01-XG QD640-XG
VMS (11/780) TU58 QES01-XG QE640-XG

Major Features

The LXY family's main features are:

Printing and Graphics Features

In both the LXY12 and the LXY22, printing is accomplished by a bank of spring hammers. The LXY12 hammer bank has 44 hammers, while the LXY22 has 66. These hammers, mounted on a shuttle, are positioned horizontally at every third character position for the LXY12 and every second position for the LXY22. As the shuttle sweeps the hammers back and forth across the character positions, the hammers are activated at each position in which a dot is required. Each hammer prints a single dot.

Printing

The LXY family of graphics lineprinters achieves excellent print quality by overlapping dots of 0.05 centimeters (0.02 inches) in diameter, on a dot matrix of nine-by-seven dots or nine-by-nine dots, anywhere on a page. The nine-by-seven matrix enables the printer to overlap dots both horizontally and vertically resulting in solid-looking characters and lines produced with uniform density. The nine-by-nine matrix is used for lower case letters with descenders, such as the letters "p", "q" and "y".

Double-height characters, as well as underlining are standard features with the LXY12/LXY22.

The LXY12 produces high-quality print at speeds of up to 300 lines per minute, 240 lines per minute when underlining or printing lowercase characters with descenders, and 170 lines per minute for double-height characters.

High-speed output of 600 lines per minute is provided by the LXY22 and is suitable for draft and data printing. When underlining or printing lowercase characters with descenders, the output is 465 lines per minute. The LXY22 prints double-height characters at the rate of 320 lines per minute.

When used as plotters, the LXY plots up to 42 centimeters per minute (16.7 inches per minute), while the LXY22 plots up to 84.6 centimeters per minute (33.3 inches per minute). Since the LXY12 and the LXY22 print overlapping dots anywhere on the page, plots are always sharp and uniformly dense.

By printing dense, overlapping dots, the LXY12 and LXY22 graphics lineprinters produce clear characters.
The LXY12 and the LXY22 are ideally suited to provide hardcopy output of designs created on a graphics terminal.

Character Sets

The LXY12/LXY22 prints the full 94-character printable ASCII set. Character form is electronically determined by codes stored in PROM devices, which are accessed by the received character codes. Up to 160 different characters may be printed by installing additional PROM devices. Optional character set PROMs includes EBCDIC, Katakana, Farsi, Arabic, Hebrew, Greek, Cyrillic and special character sets, such as OCR.

Characters are printed in a line up to 132 characters wide.

Paper

The LXY12/LXY22 accept continuous fanfold edge-perforated paper between 11.4 centimeters (4.5 inches) and 40.6 centimeters (16 inches) wide. They accept single- or multipart carbon forms and can produce up to six copies of multipart carbon forms, up to a maximum thickness of 0.06 centimeters (0.025 inches).

Operator Features

Controls and Indicators

Figure 17-1 LXY12/LXY22 Front Panel Controls and Indicators

Six controls and indicators are found on the front panel of the LXY family of graphics lineprinters.

Power On/Off Toggle Switch

This switch controls application of all power to the graphics lineprinter.

Power Indicator

When the POWER toggle switch is set to ON, power is applied to the graphics lineprinter and the indicator goes on.

Paper Advance Pushbutton

While held down, this button advances the paper at the slew rate.

Check Pushbutton/Indicator

When lit, this button indicates one of the following error conditions.

The light goes out when the fault is cleared. After reloading paper, press the CHECK button and the light will go out.

Top of Form Pushbutton/Indicator

This advances the paper to the top of the next form, or to the top of the form specified by the EVFU, if loaded. This switch operates only when the printer is off-line.

8LPI Pushbutton/Indicator

This switch selects either eight lines per inch (lit), or six lines per inch (unlit). This button operates only when the printer is off-line.

On-Line Pushbutton/Indicator

This switch enables or disables printer control through the interface. When the switch is lit, the interface is enabled. The printer cannot not go on-line if the CHECK indicator is lit.

Operation

The LXY12 and the LXY22 have two internal registers: the Control and Status Register (LXCS) and the Data Buffer Register (LXDB). (Refer to Appendix J.)

When the READY bit in the control and status register is set, the graphics lineprinter is ready to accept a character from the processor.

The processor loads characters one by one into the data buffer register in the controller. The controller then transfers the characters to a 132-character data buffer in the graphics lineprinter. The line length of 132 characters corresponds directly to this 132-character data buffer.

Figure 17-2 LXY12/LXY22 System Block Diagram

The current data buffer register (LXDB) contents are automatically printed out whenever either of the two control codes (Line Feed, Form Feed) is recognized. The Line Feed (LF) code advances the paper one line while the Form Feed (FF) code advances the paper to the top of the next page. If neither of these control codes is recognized, the contents of the data buffer will automatically be printed out when it is full.

An Elongate code (0108) anywhere in a line of characters, causes the entire line to be printed double-height. To underline certain characters in a line, a Carriage Return (CR) code (0158) is sent following the line of characters, which causes the lineprinter to wait for a line of control characters specifying which of the characters in the line already sent are to be underlined. Unlike the Elongate code which causes an entire line to be printed double-height, the Carriage Return code causes only those characters specified to be underlined.

The Electronic Vertical Format Unit (EVFU) allows you, under program control, to use a variety of form lengths. By specifying a number of lines at the slew speed, you can skip to a preassigned point in the form specified by the VFU channel number. Forms may be as long as 132 lines at six lines per inch.

A Plot Mode code (0058) anywhere in a line of characters causes the lineprinter to plot the entire line instead of print. When plotting, only one row of dots is printed at a time, and the paper advances only one dot row with each Line Feed code (0128). The characters are printed as a stream of binary bits; that is each 1 bit prints as a dot and each 0 bit prints as a blank dot space.

Special Nonprinting ASCII Control Codes

More information on this subject can be found in Appendix A.

Elongate (0108)

The Elongate code, sent anywhere in a line of characters, causes the entire line to be printed double-height.

Carriage Return (0158)

The Carriage Return code is used for underlining. It causes the lineprinter to wait for a line of control code characters (Underline, Delete or Space) before printing out the line of characters already in the data buffer register. Each control code character sent corresponds to a data character currently in the data buffer register. An Underline (1378) control code character causes the lineprinter to underline the corresponding data character. A Delete (1778) control code character causes the lineprinter to replace the corresponding data character with a blank space, and a Space (0408) control code character causes the lineprinter to print the corresponding data character unchanged.

Shift Out (0168)

The Shift Out code causes all subsequent characters to be selected from the optional character set on the PROM currently in use.

Shift In (0178)

The Shift In code causes all subsequent characters to be selected from the ASCII character set. A Shift In is automatically generated at the end of every line.

Shift to 8 LPI (0068)

The Shift to 8 LPI code causes the next Line Feed code (0128) to advance the paper one-eighth of an inch for eight lines per inch spacing instead of the standard six lines per inch. The lineprinter automatically resets itself to 6 LPI after the Line Feed operation. Shift to 8 LPI is only operational when the 8 LPI switch on the lineprinter is set to 6 LPI.

Plot Mode (0058)

The Plot Mode code (0058) sent anywhere in a line of characters causes the lineprinter to plot the entire line instead of printing ASCII characters. There are 1,583 dot positions across the width of the paper, that is, 12 dot positions for each of the 132 characters. Plot Mode allows the printing of only the odd-numbered dots or six dots per character. Bits 0-5 of each character correspond to the six printable dots of that character space. The characters are printed as a stream of binary bits; that is each 1 bit prints as a dot and each 0 bit prints as a blank dot space. For instance, printing 1018 (01 000 0012) causes only dot number 1 to be printed for that character; printing 1028 (01 000 0102) prints dot number 3; and printing 0558 (00 101 1012) prints dot numbers 1, 5, 7 and 11. Codes 1008-1378 must be used instead of codes 0008-0378, which cannot be used to plot data because they are control codes and will be interpreted as such, that is, Line Feed (0128).

Double Density Plot Mode (0048)

The Double Density Plot Mode (DDPM) code allows printing of all of the even dot positions. A DDPM code sent anywhere in a line of characters causes the lineprinter to plot the entire line instead of printing ASCII characters. Double Density Plot Mode allows the printing of only the even-numbered dots or six dots per character. Note that the Line Feed code at the end of the line of characters does not cause the paper to advance. The DDPM code must always be followed by a Plot Mode Code (0058), which fills in all of the odd-numbered dot positions.

Start Load (0368)

The Start Load code initializes the EVFU and causes all subsequent characters to be loaded into the EVFU buffer.

Stop Load (0378)

The Stop Load code indicates the end of the characters to be loaded into the EVFU buffer. The EVFU buffer allows storage of a Vertical Tab Stop code (channel) for each line of the form. Forms may be up to 132 lines long. Vertical Tab Stops are codes 0208-0358. A Vertical Tab Stop code sent anywhere in a line of characters causes the paper to advance to the next PVFU line indicated by that Vertical Tab Stop code at the next Line Feed code. Top of Form code 0208 is always loaded into line 1 in the PVFU buffer.

Interrupts

The LXY12/LXY22 system controller uses bus request (BR) interrupts to gain control of the UNIBUS to perform a vectored interrupt, which causes the program to branch to an interrupt service routine. A BR interrupt can occur only if the INTERRUPT ENABLE bit in the control and status register is set. Once the INTERRUPT ENABLE bit is set, an interrupt request is generated whenever either the READY or ERROR bits in the control and status register is set.

When the READY bit is set, the graphics lineprinter is ready to accept a character to be loaded into the data buffer register (LXDB). When the ERROR bit is set, it indicates that some error condition exists. In this case, an interrupt is generated to cause the program to branch to an error-handling routine.

The interrupt priority level is 4 and the interrupt vector address is 200. Note that the priority level can be changed with a priority plug, and the vector address can be changed by jumpers in the interrupt control logic. However, any of Digital's programs or other software referring to the priority level or interrupt vector address must also be changed if the priority plug or the vector address is changed.

Maintenance

Quality assurance means long life expectancy, high-quality output, and continuous smooth performance by your LXY graphics lineprinter. Special design features of the LXY family of lineprinters give these systems qualities of high reliability as well as ease of maintenance.

Self-test procedure

Depressing the CHECK and PAPER ADVANCE buttons simultaneously causes the LXY series of graphics lineprinters to print lines of "E". This continues as long as you hold the buttons down. If lines of "E" fail to print, contact your local Digital field service representative for assistance.

Additional Documentation

The following documents contain more detailed information about the LXY family of graphics lineprinters.

LXY Printer User's Guide (EK-LXY22-UG)
tells you how to use, maintain, troubleshoot and configure the LXY family.
LXY Installation Guide (EK-LXY22-IN)
tells you how to install, maintain, troubleshoot and configure the LXY family.

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. This document is designed to help you select the right Digital product. European versions are also available.

If you require information not contained in these documents, contact your local Digital representative, dealer, or distributor.

Specifications

Performance Characteristics

Printing speed
LXY12 300 l/min;
240 l/min for underlining or lowercase characters with descenders;
170 l/min for double-height characters
LXY22 600 l/min;
465 l/min for underlining or lowercase characters with descenders;
320 l/min for double-height characters
Plotting speed
LXY12 42.4 cm/min (16.7 in/min);
21.1 cm/min (8.3 in/min) for double density plotting
LXY22 84.6 cm/min (33.3 in/min)
42.4 cm/min (16.7 in/min) for double density plotting
Print technology Impact, dot matrix
Print density 9 × 7 (uppercase)
9 × 9 (lowercase)
Line spacing 6 or 8 l/in
Graphics 60 dots/in, horizontal
72 dots/in, vertical
Paper slew speed
LXY12 20.3 cm/s (8 in/s)
LXY22 40.6 cm/s (16 in/s)
Character set 64, 96-character ASCII (printing and nonprinting characters)
Buffer capacity 132 characters

Paper

Type Fanfold
Dimensions 11.4 cm - 40.6 cm (4.5 in - 16 in)
Multipart forms Up to 6 parts, fanfold carbon
Thickness 0.06 cm (0.025 in)

Communications

Data interface Parallel-bit ASCII code
Data interface options RS232-C buffered serial interface;
Serial-line interface

Power Requirements

LXY AC line voltage/frequency 85 - 132 VAC, at 60 Hz
170 - 264 VAC, at 50 Hz
Interface (controller) current 1.5 A at 5 Vdc
Power consumption 200 W, standby;
450 W, nominal;
800 W, maximum
Heat dissipation 1,535 Btu/hr

Operating Environment

Temperature 10°C - 38°C (50°F - 100°F)
Relative humidity 30% - 90%

Physical Characteristics

Height 118 cm (46.5 in)
Width 76.2 cm (30 in)
Depth 61.6 cm (24.3 in)
Weight 90.7 kg (200 lb)