[_CD8_]<press>PRESSOPS.BRAVO!1

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Press Printer Operation

XEROX
PALO ALTO RESEARCH CENTER
Computer Sciences Laboratory
March 24, 1977

To:Press Users

From:Bob Sproull

Subject:Press Printer Operation

Filed on <GR-DOCS>PressOps.Ears

This memo outlines the procedures for printing Press files on the Slot/3100 printers at PARC. It is also a reference manual for the Press program, and includes detailed instructions concerning its use.

Printing at PARC

Two Slot/3100 printer combinations are installed on the second floor: one is in the Graphics Lab (Room 2069); one is in the Polos Lab (Room 2026). During normal working hours, one machine or the other will be on, warmed up, and ready for use. It will be marked clearly "Service Machine." The other machine is maintained primarily for backup purposes.

During normal working hours: If neither printer is up and running (a running printer is characterized by a glow emanating from the laser housing), see the section labeled "Trouble Reporting." Otherwise, print your files!

During off-hours: If neither printer is up and running, you should turn on the printer labeled "Service Machine" and print your files. Please follow the procedure outlined in the section "Powering Up and Down."

1. Printing Press Files

The Press printing program is named "Press," and is run by hand (i.e., it is not a server like EARS). Therefore, you should boot the disk and use FTP to retrieve the file you wish to print. Because the disk is shared by many users, it is considerate to delete your Press file after you have finished printing.

The basic command to Press is "Print," followed by a file name. Thus

>Press print memo-1.press

will invoke the process of printing the file "memo-1.press." The Press command words (e.g., "print" above) can be abbreviated as long as they remain unambiguous.

If you wish to override the number of copies specified in the Press file (usually 1), append the clause "copies n" to the end of the command:

>Press print memo-1.press copies 3

If you wish to print certain pages selectively, you may append the clause "page n" or "pages n to m" to the command:

>Press print memo-1.press page 2
>Press print memo-1.press pages 3 to 4

Press takes some time to format the files properly and begin printing. If you simply wish additional copies of a file you have previously printed, you may avoid the formatting delay by using the "reprint" clause in place of the "print file" clause:

>Press reprint page 2
>Press repr cop 2

Additional commands are explained in the "Press Reference Manual," below.

Troubles While Printing

Press lets you know that it is working by flashing a cursor at you. The top of the cursor displays a character denoting the pass (F=font, S=prescan, C=scan convert, P=print) and a digit denoting the page number it is working on.

If the 3100 runs out of paper, the cursor will display the code "K1" (for "key operator") in the cursor. Add more paper to the tray, and hit the <return> key.

If the 3100 jams, the code "K2" will be displayed in the cursor. The procedure for clearing jams should be followed carefully; it is easy to throw the optics out of alignment when clearing jams. A single black knob to the right of the output hopper (knob is labeled "Release") should be turned counter-clockwise until a click is heard. Now the biege plastic housing can be raised (gently!) by lifting just above the output hopper. Raise it just enough to reach in and clear the paper jam. Now carefully lower the beige top and lean on it gently until a click re-engages the release. If you slam the top down, the alignment may suffer. Hit the return key; Press may or may not reprint the pages that were jammed.

Other 3100 malfunctions cause the code "K0" to appear. Unless it is clear what to do to make the printer ready (e.g., turn it on!), you should summon help.

2. Powering Up and Down

The Helium-Cadmium laser on the Slot/3100 has a limited life (about 1000 hours) and a non-trivial replacement cost (about $1000). The life of the laser can be shortened considerably by failure to observe some simple precautions. Please follow the procedures carefully.

Be sure, before turning power on, that the laser has been off for at least 20 minutes: if the kitchen timer on top of the machine is not ticking, you may assume that the machine has been off long enough.

Powering Up

1. The Alto. Make sure that a Model 31 disk pack labeled "Current Press Program" is in the machine and loaded. If the disk will not boot or if it demonstrates other bad behavior, there is no sense in continuing.

2. The Trident drive. If the green light on the front of the drive is illuminated, a pack is mounted and running. The chances are excellent that this is the Press pack and that you can proceed to step 3. If you doubt, read on:

Make sure power is on: If the Trident drive is making no noise whatsoever, the power is off. At the back of the drive is a toggle switch that should be flipped up to the "on" position. Noise should ensue.

To dismount a pack: Flip the black switch next to the green light to the "stop" position, and wait for the green light to stop flashing. Open the cover of the drive carefully by releasing the latch near the forward edge of the lid. Now you are in a position to read the label on the top of the disk pack. If you wish to remove the pack, retrieve the plastic pack housing (the top part, with the handle), lower it slowly over the pack, and carefully rotate the handle counter-clockwise ("unscrewing") until faint clicks are heard repeatedly. Now carefully lift the pack out by the handle and place it on the pack housing base.

To mount a pack: Retrieve the pack in its housing, and remove the base. Lower the pack into the Trident drive, and turn the handle clockwise ("screwing in") until it stops. Do not over-tighten. Now lift out the pack housing by the handle. Close the lid to the Trident. Flip the black switch from "stop" to "start." The green light should flash for several seconds and the remain lighted. If this is not the case, something is wrong.

3. The Slot/3100. If the laser housing is emitting a faint glow, the power is on and you need not embark on this section.

Raise the black circuit breaker labeled "main power," taking care not to lean on the laser housing; three lights on the panel should light. The laser will take about 30 minutes to warm up; don’t count on high printing quality for a while. Please sign the log when you turn on power.

Powering Down

If you anticipate using the printer within 1/2 hour, do not bother to power it down. If the anticipated idle time is longer, please power down to increase the laser life.

The power to the Slot/3100 is turned off by lowering the black circuit breaker labeled "main power." Please set the kitchen timer on top of the machine for 20 minutes. Please sign the log and record the values of the elapsed time meter and the Copy B counter.

Power for the Alto and Trident disk drive is normally left on.

3. Trouble-Shooting and Trouble Reporting

Hardware

Bill Winfield (x4375, Room 2027) is responsible for the hardware on both printers. Hardware problems should be reported to him. (He will summon aid for the xerographic parts of the equipment if he feels it is warranted.)

Service Machine off during normal working hours. Please summon Bill Winfield to turn on the machine. If he is unavailable, you may turn the machine on, following the procedure given above. It can be left on for the remainder of the working day. Please, if you turn the printer on, check to see that it is off before you leave for home.

Quality. If the printing quality is unacceptably low, please do not attempt to jiggle components of the 3100 (dangers of various sorts, including low citizenship marks, lurk inside the machine!). Instead, try to find Bill and ask him to help.

Inoperable 3100. If you have had no luck printing files, and suspect that the laser may not be operating properly, there is a way to print a test chart without requiring any Alto software. Flip the small toggle switch labeled "video" to the "int" position; make sure the "print quantity" indicator on the 3100 panel says "1"; and push the green "start print" button. A page with a grid test pattern should emerge from the machine. Be sure to return the "video" switch to the "ext" position.

Chaos. If you suspect that a misguided individual has fiddled with switches on the front panel, they should be in the following positions:

VideoExt
Copy ModeLandscape
Scanner Speed2
System PowerOn (Warning: this turns the laser on and off too!)
ModuOff
ScannerOn
ShutterOpen

Software

Bob Sproull (x4417, Room 2091) is responsible for the Press printing program and for the contents of the standard Alto and Trident disk packs provided for public use. Problems should be reported to him.

"Wrong" pages. If Press prints your document, but it doesn’t seem to have the right things on it, it may be that the Press file was invalid in some trivial way that the program forgave. You can run Press again, with the "verbose" mode enabled, and see if it indicates any problems. To invoke "verbose" behavior, use the /V switch:

>Press/V pri memo-1.press

Illegal Press files. If Press complains that your file is illegal, you should of course suspect the method used to generate the file! The program ReadPress, which prints on your screen a quasi-intelligible dump of the Press file, may be helpful in tracking down the problem. The command

>ReadPress memo-1.press

will bless you with more information that you can handle!

Bugs. In the unlikely event that you suspect the author of the Press software, please save your Press file on MAXC and send a message to SPROULL that gives the name of the file. Your humble servant will look into it.

Press Reference Manual
Press version 1.3

The repertoire of Press commands offers several options when a file is printed. The format of the command line is:

>Press/switches option <arg> option <arg> ...

The "switches" govern the overall operation of Press; the "options" label the specific options being used and can be abbreviated as long as they remain unambiguous; most of these options require arguments.

Options:

PrintThis is the main command to print a Press file. The argument is the name of the file to be printed. Example: "Press print memo-1.press".

CopiesThis option takes a single number as an argument, and is used to control the number of copies of the document that should be printed. Default is "Copies 1."

PagesThis option governs which pages of a file will be printed. Standard use is with the "to" option: "Press print memo-1.press pages 2 to 3". If the page range does not match the page range of the Press file, the largest overlap of the two ranges is printed. Default is "pages 1 to 99999."

RePrintThe file most recently printed is re-printed -- this usually avoids time-consuming scan-conversion processes. The "Pages" and "Copies" options apply to reprinting.

XOffsetThis option allows the page to be displaced in the X direction on the page, by an amount given by the argument (in inches). Example: "Press print memo-1.press xoffset 1.5". Default is "Xoffset 0."

YOffsetThis verb is analogous to XOffset, but governs displacement in the vertical direction.

ScreenThis option overrides default settings for halftone screen frequency. The argument is the number of halftone dots per inch.

AmplitudeThis option overrides default settings for halftone screen amplitude (normally 100%). The argument is expressed as a percentage of the image signal being halftoned.

AngleThis option overrides the default setting for the angle of the halftone screen used. The argument is given in degrees.

ResolutionThis option allows a user to override the default setting of the resolution of the output device being used. Be warned that changing resolution will usually require all your fonts to be scan-converted anew, a very time-consuming process. The argument is the resolution, measured in bits per inch.

PatternThe command "Press pattern" will scan-convert, but not print, an 8-page file of test patterns. The pages can be printed using the "press rep page n" commands.

Switches:

Several global switches can alter the use of Press:

/VVerbose -- gives better error messages

/SRe-start with the "preScan" pass
/CRe-start with the "Conversion" pass
/PRe-start with the "Print" pass (same as "reprint")
/DDebug -- shows output on display rather than printer
/MMeter -- inverts the normal setting of statistics-taking
/UMicroCode -- inverts the normal setting of using microcode
/IInstall Press

Installing Press

The command "Press/i" is used to "install" Press. This process sets a large number of parameters and initializes all the necessary Press scratch files. This section attempts to explain the procedure used for getting it all going.

Output Devices

Presently, Press can deliver its output in one of three ways:

1. To a ROS through the "Slot/3100 controller card," which is capable of generating video at rather high bandwidth (as high as the Alto and disks are capable). Press requires that you have a Trident disk to use for buffering the raster image for a page.

2. To a Versatec plotter through the Diablo printer interface. Press still requires a disk to buffer the page image, but the disk may be a Model 31.

3. To the Alto screen. This option is invoked by running Press with the /D switch. For example:

Press/d print mouse.press

Because the full image generated by Press may not fit on the screen at one time, you must type the RETURN key to sequence through the image. You may type SHIFT SWAT any time you get bored with the process.

Additionally, the output raster may be generated for a "portrait mode" or "landscape mode" scanning arrangement. For "portrait mode", scan-lines are horizontal (if the 8.5 x 11 piece of paper is held as for normal reading) and are scanned from left to right; successive scan-lines proceed from the top to the bottom of the page. For "landscape mode," scan-lines are vertical (if the 8.5 x 11 piece of paper is held as for normal reading) and are scanned from bottom to top; successive scan-lines proceed from the left to the right of the page. (In the notation of the Press <<Set-mode>> command, portrait corresponds to mode 3 and landscape to mode 8.)

Disks

Press can build its scratch files on either Model 31 disk (drives 0 or 1) or on a Trident T-80 disk. In both cases, a "file system" must have been created on the disk before Press can be installed. The easiest way to create a file system on a Model 31 disk pack is to use the "erase a disk" option when installing the operating system (but don’t burden the disk with a lot of files if you want the space available for Press use). The TFU command "erase" can be used to initialize a T-80 pack with a file system.

Files

Press requires a number of files in order to operate properly:

..the Press file you wish to print.. (%)

Press.Run (* %)
Press.Errors (* %)
Press.State (* %)

Press.Fonts (*)
Press.Bits
Press.Scratch
Press.LO1
Press.LO2
Press.Bands
Press.Meter

The files marked with * are files that you must provide before beginning to install Press; the remainder are scratch files that will be created if necessary. Files marked with % must reside on the Model 31 drive 0 disk (the system disk).

Press.Run. This file may be retrieved from MAXC, where it is stored as <PRESS>Press.Run. It is approximately 50K words long.

Press.Errors. This small file may be retrieved from MAXC, where it is stored as <PRESS>Press.Errors.

Press.State. This tiny file contains the results of installing Press. Initially, you may wish to copy it from MAXC (<PRESS>Press.State) in order to see how Press is normally installed for the Slot/3100.

Press.Fonts. This file must be initialized to contain all the fonts you wish to make available for printing. The file is in the format of a "PrePress dictionary," and can be built and manipulated with PrePress (see <GR-DOCS>PrePress.Ears for documentation). The file may contain spline descriptions of fonts as well as scan-converted fonts. The splines are useful in case a particular Press file requires a font size or rotation that is not in Press.Fonts in scan-converted form. The scan-converted forms are useful because they can be accessed more rapidly (scan-conversion is not required), and because they may be touched up with PrePress. An example of creating Press.Fonts is given below.

Note: If Press.Fonts is placed on a Trident disk, it should be allocated in a contiguous hole of disk space. In order to achieve this, use PrePress to make the dictionary you desire, and call it Press.Dict. Then, after PrePress operations are complete, give the command "TFU copy Press.Fonts/C ← Press.Dict" which will copy Press.Dict into Press.Fonts and will try to allocate Press.Fonts on consecutive disk addresses.

Press.Bits. This scratch file is used to buffer the raster image for pages to be printed by Press. This file can be as big as you like, but must be at least big enough to hold one full-page image. This minimum is computed as (k(s+15)/16l)(k(32k(b+31)/32l+1023)/1024l) K words, where s is the number of scan-lines on the page, and b is the number of bits per scan-line.

If Press attempts to print a Press file with enough pages to overflow the buffering available in Press.Bits, Press will break up the scan-conversion and printing passes into several segments. First it will scan-convert pages until it exhausts the buffering in Press.Bits, then it will actually print those pages on the output device. Then it will repeat this sequence until the entire file has been properly printed. Note that this process may destroy the collation sequence.

Press.Scratch. This scratch file is used for (1) font information for the file being printed, including any fonts that have been scan-converted from splines just for the one file being printed and (2) <Show-dots> images that must be rotated in order to conform to the scanning directions of the printer. For example, if you print a Markup-created Press file which contains a dots image (mode=3) on a "landscape" mode printer, the image will be rotated and saved in Press.Scratch. A full-screen Alto image requires about 32K words. A recommended size for Press.Scratch is (10+ 32n) K words, where n is the number of Alto screen images you expect in the largest file.

Press.LO1 and Press.LO2. These scratch files are used during the scan-conversion process when a page becomes excessively complex. They may be quite small (e.g., 1K words), and can be expanded if you encounter such a complex file. Because of their small size, it is marginally advantageous to locate them on a Model 31 disk rather than on a Trident disk.

Press.Bands. This scratch file contains the results of the pre-scan pass over the Press file. Its size is roughly (2c + 5r + 80s)/1024 K words, where c is the total number of characters in the Press file, r the total number of rectangles, and s the total number of splines (<<Drawto>> or <<Drawcurve>>).

Press.Meter. This scratch file holds statistical information about Press files as they are printed. I don’t recommend that anyone other than myself attempt to decipher the information. Consequently, you should disable the recording of metering information when you install Press. However, the file Press.Meter must exist in any case, although it can be of negligible length (1K words).

The list of files gives a rough idea of appropriate sizes (remember that a "disk page" is 0.25K words on a Model 31 and 1K words on a Trident). I typically use the following sizes on a Slot/3100 installation running at 384 bits/inch:

Press.Bits14400 KTrident (14400 pages)
Press.Scratch2000 KTrident (2000 pages)
Press.LO125 KModel 31 (100 pages)
Press.LO225 KModel 31 (100 pages)
Press.Bands1000 KTrident (1000 pages)
Press.Meter1 KTrident (1 page)

It is not essential that you get the file sizes exactly right. If Press exhausts one of the files during operation, it should generate a reasonable error message that identifies the short file. You can then re-install Press to enlarge the file, and try printing again.

Building Press.Fonts

The easiest way to initialize Press.Fonts is to copy it from someone else who has already done the work. The Slot/3100’s at PARC both have Trident disks with a rather complete repertoire already in Press.Fonts (for 384 bits/inch, landscape printing mode).

If you build you own, you will need to master the PrePress program (documentation on MAXC is <GR-DOCS>PrePress.Ears). You can start from ".SD" files stored on the MAXC directory <PRESSFONTS>. These files are in "SDtemp format," and contain encoded spline descriptions of various font families. You can then use PrePress to scan-convert them for the proper resolution of your device, and for the proper scanning orientation (if your printer runs in "landscape" mode, you need say nothing special to PrePress; it if runs in "portrait" mode, you need to add 90 degrees to the rotation you would normally request).

Because making a font dictionary takes quite a while, it is best to compose a command file with a text editor, and then execute the command file while you wander off to greener pastures. Standard command files for building 3100 fonts may be found on <PRESSFONTS>FontCommands.Dm.

The normal practice I use is to assemble the fonts in a file called Press.Dict, and then at the end to copy that file to Press.Fonts. This is necessary on the Trident, because Press.Fonts must be a consecutively-allocated file. Consequently, after making Press.Dict (see examples below), I do the following:

//First, delete old Press.Fonts
TFU delete Press.Fonts
//Now copy Press.Dict into Press.Fonts, consecutively allocated:
TFU copy Press.Fonts/c ← Press.Dict

Example 1. Here is a command sequence to make a Press.Fonts with a reasonable complement of TimesRoman fonts:

//First, delete the dictionary
Delete Press.Dict
//Now get TimesRoman.Sd and name it SDtemp on the Alto
Ftp maxc r/s <PRESSFONTS>TimesRoman.Sd SDtemp
//Merge the splines into the dictionary
PrePress merge/s Press.Dict/b
//Convert an 8-point font at 350 bits/inch
PrePress convert 8/p 3500/d
//Merge this scan-converted font into Press.Dict
PrePress merge/c Press.Dict/b
//Convert a 10-point font
PrePress convert 10/p 3500/d
PrePress merge/c Press.Dict/b
//...and so forth
PrePress convert 12/p 3500/d
PrePress merge/c Press.Dict/b
//Now do the italics
Ftp maxc r/s <PRESSFONTS>TimesRomanI.Sd SDtemp
PrePress merge/s Press.Dict/b
PrePress convert 8/p 3500/d
PrePress merge/c Press.Dict/b
PrePress convert 10/p 3500/d
PrePress merge/c Press.Dict/b
PrePress convert 12/p 3500/d
PrePress merge/c Press.Dict/b
//...and so forth... with TimesRomanB.Sd and TimesRomanBI.Sd
//We can verify what we have by listing the dictionary:
PrePress list Press.Dict/b
Type PrePress.Lst

Example 2. Some of the fonts do not have italic or bold italic versions of the splines. In this case, use the "fake italic" option of PrePress when converting (15% is about right):

Ftp maxc r/s <PRESSFONTS>Gacha.Sd SDtemp
//...go ahead and make the "normal" Gacha fonts
// When it comes time for italics:
PrePress rename/s mir/f
PrePress convert 8/p 15/i 3500/d
PrePress merge/c Press.Dict/b
//...etc...

Example 3. Making fonts for a portrait-mode printer:

Ftp maxc r/s <PRESSFONTS>TimesRoman.Sd SDtemp
//It still makes sense to include the splines:
PrePress merge/s Press.Dict/b
//Make an 8-point font -- notice the rotation
PrePress convert 8/p 3500/d 90/r
PrePress merge/c Press.Dict.b
//...etc...

If you want to merge in both landscape and portrait fonts, use the PrePress "rotate" command (it saves a bit of time):

Ftp maxc r/s <PRESSFONTS>TimesRoman.Sd SDtemp;
PrePress merge/s Press.Dict/b
//Make an 8-point font
PrePress convert 8/p 3500/d 90/r
PrePress merge/c Press.Dict.b
PrePress rotate
PrePress merge/c Press.Dict.b
//...etc...

Example 4. Using the Trident disk. If you are building a huge dictionary, the sequences given above will rapidly exhaust the available disk space on the Model 31. PrePress contains a feature for locating some of the files on the Trident:

//Need to initialize PrePress by making files of proper name but
//with length=0 on the Trident. The Alto Executive will make a zero-length
//file with the first command (which assumes the file gggg does not exist):
Copy zero ← gggg
Tfu copy PrePress.Scratch ← s:zero
Tfu copy Press.Dict ← s:zero
//Now we can merge into Press.Dict with the /T switch.
Ftp maxc r/s <PRESSFONTS>TimesRoman.Sd SDtemp
PrePress/t merge/s Press.Dict/b
PrePress convert 8/p 3500/d
PrePress/t merge/c Press.Dict/b
//...etc...

The Press installation dialog

If you have retrieved all the files necessary to run Press, made a proper font dictionary, and decided on the sizes of the scratch files you wish, you are ready to embark on the installation dialog.

Installation is invoked with the command "Press/i". Once Press has been properly installed, subsequent installation is considerably simpler: simply typing RETURN to each installation prompt will use the same value used in the previous installation--the previous value is given inside parentheses. The paragraphs below describe the various questions you will be asked. Each response must be terminated with a RETURN; typein to Press is edited by typing CTRL A to backspace one character (\ will be typed to indicate a character has been rubbed out); N RETURN is sufficient to mean No; Y RETURN is sufficient for Yes. If you make a catastrophic mistake during the installation, simply type SHIFT SWAT (or boot the machine) and begin again.

General installation parameters.

Record metering information? I recommend answering "N" to this question.

Meter each file transfer? I recommend answering "N" to this question.

Meter each character fault? I recommend answering "N" to this question.

Normally use microcode? Press uses a good deal of microcode to speed its inner loops. This microcode will work properly on Alto I (provided it has reasonably recent PROM microcode) and on Alto II. Consequently, you should respond "Y" to this question. However, if you are experiencing erratic behavior (e.g., Press dives off the deep end), you might try re-installing to turn off the microcode, and see if the situation improves.

Log statistics on MAXC? If you have any sort of network access to MAXC (e.g., a gateway), I would appreciate your "Y" response to this question.

Printer parameters. You are first asked for the name of the output device to use normally (Slot or Versatec at present). Then you are prompted for the resolution of the device in scan-lines per inch and in bits per inch (these are usually the same). The subsequent dialog depends on the output device selected:

Versatec. If you select the Versatec, Press assumes that output will be in portrait mode. You are asked for the number of bits on a scan-line: the response depends on which model plotter you have (e.g., 900A is 1600). It is essential that this response be accurate.

Hg (Mercury printer). This option drives a TC 200 printer, as modified by Bob Hunt at ADL.

Slot. The following questions are asked for all devices that use the "Slot/3100 card" to drive a ROS:

Does the first page printed emerge at the top of a stack? The answer to this question is used to control the sequence in which pages are actually printed, so that the final stack of pages will be collated properly.

Does the Slot run in portrait mode? See the discussion above. Note that if you respond "Y", you will probably want a Press.Fonts font dictionary that contains 90-degree rotated fonts for rapid access.

Scan-line length in bits (for Slot)? This prompt requires a number that is used to control the Slot interface on the Alto. It determines how many "bits" are to be evenly spaced between the start-of-scan pulse and the end-of-scan pulse emanating from your ROS equipment. Note that it does not govern how Press builds the raster image, but only how the hardware lays it down on the page. Incorrect settings of this number may cause the beam to be "off" when it passes over the end-of-scan detector, with consequent chaos.

Scan margin adjustment? This number governs how many scan-lines Press passes up, after your Slot transmits "page sync," before the image is actually begun. Fiddling with this number will adjust the position of the image on the page.

Bit margin adjustment? This number offsets the position of the image along the scan-line (the response is rounded down to the next multiple of 8). Fiddling with this number will adjust the position of the image on the page.

Do you want scan-lines doubled? If you respond "Y" to this question, the Slot card will transmit each scan-line to the ROS twice. Thus, you can declare to Press that your ROS operates at 384 scan-lines per inch, but by doubling each scan-line, you can operate a ROS that actually runs at 768 scan-lines per inch. (If you use this option, your Slot/3100 card may need a slight modernization. Instructions are available from the author.)

What should the timeout be? This parameter allows you to specify the time, in seconds, that Press will wait for the Slot interface to finish delivering its output to the printer for one page. If the time is exceeded, Press will generate an error K0.

Paper parameters. For most printers, the long dimension of the paper is "11.0" and the short is "8.5".

Halftone parameters. Press contains code for applying a halftoning algorithm to continuous tone images that appear in Press files. The three prompts in this section allow you to set the screen frequency (80/inch on 384 bit/inch printer is reasonable), the screen amplitude (100% is reasonable), and the screen angle (usually 45 degrees is best).

Disks. Press will ask if you want to use the Trident disk, and if so, which drive number (0 if you have only 1 drive). It will also ask if you want to make use of drive 1 of the Model 31 controller.

Files. Now Press will cycle through all the scratch files, asking you to specify the treatment for each one. If a file already exists, its location and size are printed, and you are asked if that is proper ("Y" or simply RETURN implies Yes). If you respond that the allocation is not proper, or if the file does not exist, Press prompts to determine which disk the file should use, and how big (in disk pages for the disk you select) the file should be.

Hints for the Hardy

1. Avoiding the font pass. If you are printing a Press file that you know has no characters in it, you may profitably omit the "font pass." In most cases, this buys you very little, because the font pass simply looks up fonts in a large index in Press.Fonts. However, if the Press file requires fonts that are not readily available in scan-converted from, the font pass may take a long time to scan-convert the characters from splines. It is this latter time-consumer that you can bypass if you know the document will not use any of the characters. Simply use the /S switch to begin operation on the prescan pass. For example:

Press/s print image.press

This trick is often useful in conjunction with temporary resolution changes:

Press/s resol 363 print image.press

Warning: This little trick will not work on the very first document after Press is installed.

2. Aligning Press for your ROS. The Press file saved as <PRESS>Align.Press will print a one-page test pattern that has triangular shapes pointing into the corners of the page. This file is provided to help adjust the "Scan margin adjustment" and the "Bit margin adjustment."