home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
Software 2000
/
Software 2000 Volume 1 (Disc 1 of 2).iso
/
printer-studio
/
star-drivers
/
readme
< prev
next >
Wrap
Text File
|
1995-01-01
|
85KB
|
2,004 lines
COPYRIGHT
=========
This program copyright 1993 by Wolf Faust. All rights reserved.
This product is subject to propriety rights. Installer and
Installer project icon (c) Copyright 1991-93 Commodore-Amiga, Inc.
All Rights Reserved. Reproduced and distributed under license
from Commodore. More (c) Copyright 1986-93 Commodore-Amiga, Inc.
All Rights Reserved. Reproduced and distributed under license
from Commodore.
DISCLAIMER
==========
THE DRIVER HAS BEEN PROVIDED TO YOU STRICTLY 'AS IS', WITHOUT
WARRANTY OF ANY KIND. IN NO EVENT SHALL STAR MICRONICS OR FAUST
BE HELD LIABLE FOR ANY LOSS OR DAMAGES ARISING OUT OF ANY ACTION,
FROM WHATEVER SOURCE, CONCERNING THE USE OR INABILITY TO USE THE
DRIVER. SAVE IN RESPECT OF DEATH OR INJURY ARISING OUT OF THE
NEGLIGENCE OF STAR MICRONICS OR FAUST.
INSTALLER SOFTWARE IS PROVIDED "AS-IS" AND SUBJECT TO CHANGE; NO
WARRANTIES ARE MADE. ALL USE IS AT YOUR OWN RISK. NO LIABILITY
OR RESPONSIBILITY IS ASSUMED. THE More PROGRAM IS PROVIDED
"AS-IS" AND SUBJECT TO CHANGE; NO WARRANTIES ARE MADE. ALL USE IS
AT YOUR OWN RISK. NO LIABILITY OR RESPONSIBILITY IS ASSUMED.
Trademarks
==========
Amiga is a registered trademark of Commodore-Amiga, Inc.;
All other trademarked products and company names used herein are
used for identification purposes only. No infringement of
trademarks is intended. Trademarks remain the property of the
trademark holder.
Welcome to the Star Driver
==========================
The Star driver is a software for controlling a printer with the
Commodore-Amiga personal computer with the purpose of creating
high quality output. The driver's main qualities include:
o Freely definable dither routines (many are included).
o 16-point colour adjustment for each colour component. This allows
you to do gamma correction, adjust the contrast and brightness,
plus more.
o Ink compensation for the correction of ink impurities.
o Workbench 2/3 graphical user interface (GUI).
o The driver can print up to 256 shades of grey from normal
Amiga applications. Standard Amiga drivers are limited to 16.
o Full control over page size, paper margins and size of the printed
graphics.
o Full control over built-in printer typefaces.
o The software is very fast and automatically uses improved routines
if the software is run on an Amiga with a 68020/30/40 CPU.
o Builtin support for the arXon electronic centronic switch box.
o Free definable tab stops.
o Job end signal.
o Supports Workbench 1.3, 2.0, 2.1 and 3.0.
These are not the complete capabilities of the Star drivers,
merely some highlights.
System Requirements
===================
The software is compatible with the entire family of Amiga
computers. These include the A500, A1000, A1200, A1500, A2000,
A2500, A2500/30, A3000 and A4000. The software was designed to
run under Workbench versions 2, 2.1 and 3. The printer driver
also work under Workbench 1.3, but must be controlled via the
keyboard (CLI) because Star programs with that have a GUI require
at least Workbench 2.
Installing
==========
The driver is a replacement for the Commodore supplied printer
drivers. It is a 100 percent Amiga compatible printer driver,
except that it offers many more functions than a normal printer
driver. The additional functions of the driver are controlled by
a preferences program included with Star driver disk.
The programs and driver are described in detail later. Start the
installation by a simple double click on the Install icon, found
in the main drawer of the driver disk.
You should follow the checklist below for installing the
Star software:
o Set up and connect your printer as described in the printer's
user manual and Amiga system manual.
o Ensure your printer's initial setup is configured to Epson
emulation and USA character set. On the SJ144 this is the
default factory setting. For other dot matrix printers, set
the printer dip-switches as descibed below:
Automatic line feed off
Automatic carriage return off
Emulation Epson (standard)
International charset USA (national characters are
handled by the driver
automaticly!
o Boot your Amiga with your usual system or Workbench disk.
o Double click on the Install icon found in the drawer of
the disk. The install program will copy the driver to
your system disk. In order to do so, you need 45 KByte empty
disk space on your system disk.
! Most likely floppy users must make space on their system disk in
order to install the driver. This can be done by deleting unneeded
programs using the Workbenchs 3.0 "Delete..." menu item.
Here is list of programs that might be deleted:
Sys:Utilities/Clock (13 KByte)
Sys:devs/printers/generic (1.5 KByte)
Sys:system/nofastmem (1 KByte)
Sys:c/Edit (15 KByte)
Sys:c/Diskchange (0.5 KByte)
Sys:c/Lock (0.5 KByte)
Sys:c/Search (1.5 KByte)
Sys:c/MagTape (1.5 KByte)
In case you run out of disk space, you may install the Star
preferences program on any free disk, saving you disk space on the
system disk.
o If not allready done by the installation program, start
Preferences on your system disk (if you own Kickstart 2.0
use the "printer" preference program) and select the driver
reported by the installation program. Adjust all other
preference parameters to your environment. See your system
manual for more information about the preference program.
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!Make sure "Ordered" dither and density > 2 is set in Preferences!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
After successfully running the Install program, try printing from
the application with which you normally print.
The Workbench Printer Drivers
=============================
After installing a Star driver you should be able to print from
your normal application programs. In most cases you must further
adjust the driver settings to your printer to get the best printer
output possible. Correct adjustments often lead to major quality
improvements. This chapter describes most of the functions for
controlling the Star driver. But before describing the driver in
its own special section, some general things about printer
drivers, and especially the Star driver.
Printer drivers offer a way of sending configuration-independent
output to a printer attached to the Amiga. A driver can be
thought of as a filter that takes standard commands as input, and
translates them into commands understood by specific printers.
The commands sent to the printer via the prt: device are
standardized on all Amigas so that programmers only have to write
the software once and not for all possible printer emulations. It
is the task of the printer driver to translate an Amiga printer
command into the correct command for a particular printer. For
each type of printer in use, a printer driver (or a driver for a
compatible printer) should be present in the "devs:printers"
directory.
If you want to print text in bold, you have to decide whether to
use a standard Amiga command (also known as an escape sequence)
via prt:, or the command mentioned in your printer manual via
par:. Often people get confused about prt: and par:. Do not
send commands mentioned in your printer manual to prt:. This will
most likely fail, or cause wrong characters in your printer
output. You should always prefer prt: to par: because commands
send to prt: can be used on every printer, not just the kind of
printer you have. The par: device has even more shortcomings
than prt:, but we're not concerned with them in this manual.
An often used argument from programmers using par: is the
unlimited control over the printer. This is a fallacy. You can
control every printer feature via the prt: device.
The Star Printer Driver
-----------------------
The Star printer driver automatically check for the processor
being used (68000, 68010/68020, 68030, 68040) and optimize the
print routines accordingly, so there is no need for a special
`turbo' version of the driver in order to get the most out of your
Amiga.
The tables below show the graphics densities supported by the Star
driver. Density is set in Workbench preferences. Often you can
also choose a density from within your application program.
Beside the density tables, a table with all driver-supported Amiga
escape sequences (use prt: not par: for these commands) is
shown.
StarSJ144 densities.
Density X dpi Y dpi Comment
1 180 360 no adjustments/dither
2 360 360 no adjustments/dither
3 180 360
4 180 360
5 180 360
6 360 360
7 360 360
Star24Plus with Epson 24 emulation
Density X dpi Y dpi Comment
1 360 180 no adjustments/dither *1
2 360 360 no adjustments/dither, *1, two pass
3 180 180
4 120 360 zweimal überfahren
5 180 360 zweimal überfahren
6 360 180 *1
7 360 360 zweimal überfahren, *1
Star24Plus with Epson 48 or Star 48 emulation
Density X dpi Y dpi Comment
1 360 180 no adjustments/dither, *1
2 360 360 no adjustments/dither, *1
3 180 180
4 120 360 zweimal überfahren
5 180 360
6 360 180 *1
7 360 360 *1
*1 - in this mode the printer cannot print two consecutive dots in a row.
It is recommended that you only use this density for B&W Shade dumps.
Star9Plus Treiber
Density X dpi Y dpi Comment
1 144 144 plotter graphics, no adjustments/dither
2 240 216 quadruple density, no adjustments/dither
3 120 72 double density
4 144 144 plotter graphics
5 240 144 quadruple density
6 144 216 double density
7 240 216 quadruple density
Name Sequence Function
aRIS ESCc reset
aRIN ESC 1 init.
aIND ESCD lf
aNEL ESCE return,lf
aRI ESCM reverse lf
aSGR0 ESC[0m norm.chars
aSGR3 ESC[3m italics on
aSGR23 ESC[23m italics off
aSGR4 ESC[4m underline on
aSGR24 ESC[24m underline off
aSGR1 ESC[1m boldface on
aSGR22 ESC[22m boldface off
aSFC SGR30-39 foregrd col.
aSHORP0 ESC[0w normal pitch
aSHORP2 ESC[2w elite on
aSHORP1 ESC[1w elite off
aSHORP4 ESC[4w condensed on
aSHORP3 ESC[3w condensed off
aSHORP6 ESC[6w enlarged on
aSHORP5 ESC[5w enlarged off
aDEN6 ESC[6"z shadow on
aDEN5 ESC[5"z shadow off
aDEN4 ESC[4"z double on
aDEN3 ESC[3"z double off
aDEN2 ESC[2"z NLQ on
aDEN1 ESC[1"z NLQ off
aSUS2 ESC[2v super on
aSUS1 ESC[1v super off
aSUS4 ESC[4v sub on
aSUS3 ESC[3v sub off
aSUS0 ESC[0v normal line
aPLU ESCL part. up
aPLD ESCK part. down
aFNT0 ESC(B typeface 0
aFNT1 ESC(R typeface 1
aFNT2 ESC(K typeface 2
aFNT3 ESC(A typeface 3
aFNT4 ESC(E typeface 4
aFNT5 ESC(H typeface 5
aFNT6 ESC(Y typeface 6
aFNT7 ESC(Z typeface 7
aFNT8 ESC(J typeface 8
aFNT9 ESC(6 typeface 9
aFNT10 ESC(C typeface 10
aPROP2 ESC[2p prop. on
aPROP1 ESC[1p prop. off
aJFY5 ESC[5 F auto left
aJFY7 ESC[7 F auto right
aJFY6 ESC[6 F auto full
aJFY0 ESC[0 F justify off
aJFY1 ESC[1 F word fill
aVERP0 ESC[0z 1/8" spacing
aVERP1 ESC[1z 1/6" spacing
aSLPP ESC[nt form length n
aPERF ESC[nq perf skip n
aPERF0 ESC[0q perf skip off
aCAM ESC 3 Clear margins
aTBC3 ESC[3g Clear h tabs
aTBC4 ESC[4g Clear v tabs
aTBCALL ESC 4 Clr h tabs
aTBSALL ESC 5 default tabs
aRAW ESC[Pn"r 'Pn' raw
The StarPref Preferences Programs
=================================
Beside all the functions mentioned in the section above, there are
more options unique to the Star driver. These options are managed
using Commodore's standard environment variables and can be
controlled by using the Shell "setenv" and "getenv" commands. But
setting environment variables this way can be a very complex task,
so a StarPref preferences program is available to make the job
easy.
The StarPref preferences programs provide an intuitive GUI and
requires at least Workbench 2 to run. If you are not using at
least Workbench 2 (V37 and above), you must use the Shell commands
for controlling the driver variables (described in detail in an
extra chapter on page envs ).
The StarPref preferences programs can be controlled by the mouse
and/or the keyboard. Each gadget of the program corresponds to
the underlined letter in a gadget. Pressing that letter is
equivalent to clicking on the gadget. In the case of a cycle
gadget, you can use the upper case or lower case letter to cycle
back and forth. See your system manual on how to control the file
requester by keyboard or mouse.
All windows are opened directly under your mouse pointer, so you
don't have to move or scroll the screen to control the program.
All windows are opened on the default public screen. You may
specify a special public screen by setting the Tool Type PUBSCREEN
screenname (the name is case sensitive) and the StarPref
preferences program will open its windows on your application
program's screen. You can specify a screen if you run the
preferences program from a Shell with the
StarPref PUBSCREEN screenname
For example, if you use the ASDG CEDPro text editor you may
specify "StarPref PUBSCREEN CygnusEdScreen1" and the StarPref
preferences program will open its windows on the CEDPro screen.
Make sure the CEDPro screen is public before running the example.
You need at least CEDPro version 2.12 for this example.
StarPref is independent, which means they use any system font
you have chosen in preferences for displaying the text in gadgets
and windows. You can force the preferences program to always use
the topaz 8 font by defining a TOPAZ Tool Type. This is equal to
using a TOPAZ Shell argument.
After starting the preferences program, the main window opens.
This contains several gadgets which the equivalents of the
appropriate environment variables. The names and settings of
these environment variables are covered in an extra chapter. This
chapter covers all you need to know about controlling the
driver via the StarPref preferences programs.
Each gadget of the StarPref program will now be described in
detail:
Separation
You may print separations with the help of the separation gadgets
in the upper right half of the window. Each primary colour that
is checkmarked will be printed (C=cyan, M=magenta, Y=yellow,
K=black). An example of the use of the separation function can be
found in the Tips and Tricks chapter.
Fast Graphics
If set to on (with a checkmark), the driver sends out graphics
faster to the printer. While the printing speed can be improved
significantly, printing quality may be loosed and vertical lines
may be printed misaligned. Some old Star printers do not work
with Fast Graphics turned on. To check you printer simply print a
grid (horizontal and vertical lines with 3 cm distances) of thin
black lines on white paper in density 7. With or without "Fast
Graphics", all lines should be printed the same and without any
bad alignment. The printerhead should print vertical lines in one
go and should not stop for each vertical line, as this would
result in a loss of print speed instead of increasing the speed.
Mirror
If set to on (with a checkmark), graphics will be mirrored;
especially useful if you want to print pictures intended for
T-shirt art. You can buy special ink/ribbons from various dealers
for Star printers.
Textcolor
With the Textcolor cycle gadget you may choose the default text
colour for the printer.
Typeface
The Typeface cycle gadget allows you to define the printer
typeface. "Typeface 0" selects the typeface selected with the
ESC-k-0 command of your printer (see your manual or simply try).
"Typeface 1" select typeface ESC-k-1 and so on.
Graphic Mode
The StarSJ144 driver supports two graphic printing modes. In
Epson48 mode, the drivers prints graphics using the printers Epson
emulation. The printer can print up to 48 dots per line in Epson
emulation, while the CDM mode supports up to 144 dots. You can't
print text using the printers internal fonts in CDM mode. I
strongly recommend the CDM mode for any graphic printings because
of the higher speed and quality. If you do need both, text and
graphic, you must use the slower Epson mode.
Beside the Epson48 mode, the Star24Plus driver offers two more
modes:
Epson 24 - the default 24 pin printer emulation with up to 360*360 dpi.
Star 48 - this mode is similar to the Epson 48 mode and can be used
on Star SJ48 and SJ144 printers.
Color Mode/Supergrey
Normal Workbench printer drivers are limited to 16 shades of grey.
After brightening the graphics output, even fewer shades are
available. The Star driver does not have this limitation and can
print colour pictures in up to 256 shades of grey.
With Supergrey enabled, every colour picture will be printed as a
greyscale picture if you select colour instead of greyscale as the
graphics output mode. With Supergrey it is the printer driver's
task to convert the colour data into greyscale data. While this
can be done by the printer device instead of the printer driver
(as normal Workbench drivers do), the Star printer driver
colour-to-greyscale conversion routines are more precise. Because
of this you can print a 4096 colour HAM picture in up to 256
shades of grey instead of the normal 16 shades. Supergrey will
replace the normal colour dump of the driver.
If you want to print more than 16 shades of grey (and that's what
Supergrey is all about!) you must define a custom dither matrix in
the StarPref program that enables you to print more than 16
shades. Defining a dither matrix using StarPref is described
below. As default, a 64 shade Halftone A dither is used.
Supergrey works with nearly every Amiga application simply by
printing in Workbench's colour mode, even if your printer isn't a
colour printer. Application programs that provide their own
dither routines should not be used with Star custom dither
routines, and because of this should not be used with Supergrey .
Programs with custom dither routines include Art Department
Professional's PrefPrinter saver, TruePrint24, PageStream. The
Studio picture-printing program also belongs to this category of
programs, but it automatically detects whether you are printing in
Supergrey or colour.
Supergrey can be disabled in several ways. Take care that none of
the following special cases are in effect if you want to print
pictures using Supergrey:
o Star's custom dither and colour correction routines can be
turned off by printing with a Workbench density below 3. Because
of this, Supergrey works only with graphics densities above 2.
o Star's custom dither and colour correction routines can be
turned off by printing with a Workbench dither method other than
"ordered". Because of this, Supergrey works only with the
"ordered" dither routine set in Workbench preferences. This does
not mean that you cannot print a halftone dither with Supergrey.
You just have to use the Star dither routines set in StarPref
instead of the dither routines set in Workbench preferences,
because only the Star dither routines offer more than 16 shades of
grey.
o Supergrey can always be turned of using StarPref.
The Table below shows all parameters that must be enabled for
printing with Supergrey.
Function Density Workbench dither
Supergrey >2 ordered
Colour Adjustment >2 ordered
Ink compensation >2 ordered
Driver dithers >2 ordered
Note: the number of printable shades of greys in Supergrey
depends on the number of shades supported by the dither method set
in StarPref. Up to 256 shades are possible, and supported by the
Star dither routines. Often a dither method that produces 64
shades (default) gives best results.
Timeout
Most people know the "Printer trouble..." requester well. This
system requester most often appears when you print a document that
is several pages long. The requester is caused by the computer
not transferring waiting data to the printer for a period of time
(usually 30 seconds). If there is a `timeout' the printer device
assumes an error and the requester appears. A timeout may also
appear without a real error happening if your printer is waiting
for (or slowly feeding in) a new sheet of paper, for example.
This operation often needs more than 30 seconds, and during this
time no data is accepted by the printer.
With Timeout you can specify a higher timeout value, resulting in
fewer timeout requesters. A value from 1 to 999 seconds is
allowed (default 60 seconds).
Instead of defining a huge timeout value there is another solution
available: use the CMD program (see your Workbench disk) to
redirect the parallel/serial output to a file on disk. After
this, use the Copy command or a printer spooler to copy the file
to par: . This technique may also result in a better output
quality, especially with inkjet printers.
Note: If there is a real timeout error you will have to wait the
number of seconds specified by Timeout until an error requester
appears, thus allowing you to cancel the print job. So choose
your Timeout value wisely.
Job End
If the printer device gets closed after a dump, you can tell the
driver to signal the end of the print job. This is especially
useful on huge graphic dumps which might require some time. There
are two kinds of signals. You can cause a beep (Ctrl-G) on the
printer, a DisplayBeep on the Amiga, or both.
arXon Port
The Star driver supports the arXon parallel switch-box, an
external 1 to 3 Centronics switch controllable by software. You
can ask the printer driver to automatically switch to the required
port for printing, and switch back to the previously used port
after printing. This enables you to use a scanner, a digitizer
and a printer from your Amiga's parallel port without having to
switch between the devices manually. If you specify Default as
the port, no switching will take place.
Information about the arXon switch-box may be obtained from:
arXon GmbH
Assenheimer Str. 17
D-60489 Frankfurt
Germany
Tel: 010-49-69-7896891
Fax: 010-49-69-7896878
The environment variable sbox_active must be specified before
using the driver in order to enable the switch-box feature of the
driver. This is because sbox active is used to determine whether
a switch-box is installed or not. sbox_active is defined by the
arXon software.
Save
You may leave the StarPref preferences program by clicking on the
Save gadget. Changes made to the settings will be saved for
permanent use.
Use
You may leave the StarPref preferences program by clicking on the
Use gadget. Changes made to the settings will be saved
temporarily and will stay active until you reboot the computer or
change the settings using StarPref again.
Cancel
You may leave the StarPref preferences program by clicking on
the Cancel gadget. Changes made to the settings will not be
recognised or saved.
More control windows
--------------------
There are four gadgets in the bottom half of the main
StarPref window. The ellipsis (three dots) in these gadgets
means that another window will be opened when you select the
gadget. Here is detailed description of each of the four windows.
Customize Tabulators... Tabulators
The gadgets in this window let you customize the horizontal tab
stops settings of your printer, useful for printing program
listings and tables. Up to 32 tab stops may be defined. All tab
stops above the limit of 32 are ignored, and a requester will tell
you so. Horizontal tabs are usually selected and stored by the
printer in characters, not inches. Thus, any change in the
character spacing can change the physical locations of horizontal
tabs, but the logical positions remain unchanged.
You can set or unset a tab stop by clicking in the gadget at the
required position. A 'T' is used for a tab stop. The '-' and '+'
characters are used to help you find the correct position. Using
the slider below the gadget you can scroll the `tab stops' gadgets
to the required position.
Clear Tabs
With Clear Tabs you can clear all tab stops.
Set every n chars
With the n: and Set every n chars gadgets you can easily set tab
stops with the same distance. Simply enter the distance into the
n: gadget and select Set every n chars .
Note: the printer driver uses a default distance of eight
characters. If you want to reset your customized tabs stops
settings to the printer default values, simply call up Customize
Tabs... and the window will open with a default n: value of 8.
Press "Set every n chars" to select the default value.
Use - Cancel
You can leave the window with the Use or Cancel gadget. Changes
made to the tab stops settings are accepted with Use. Cancel
leaves the tab stops unchanged, and any changes made will be lost.
Note: Use does not save the changes made to your environment.
This is done by using the Use or Save gadget in the main window.
Page Size and Margins...
The gadgets in this window let you customize the paper size and
margins. This window contains many additional settings that are
unknown to most normal printer drivers.
Enable Form
If Enable Form is checkmarked, page length (as set in Workbench
preferences), Top Margin and Perforation Skip will be enabled by
the driver. In order to stay compatible with normal Workbench
printer drivers, by default the settings are not used. Some
applications require well-defined paper sizes and margins for
printing forms. The Star driver provides you with these
facilities by checkmarking Enable Form. It may require some
experimentation (and paper) until you have found the correct
values for a specific application.
Top Margin
Number of lines for the top border of the page. This setting is
only supported by some, not all Star printers.
Perforation Skip
Perforation Skip specifies the number of lines that the printer
skips over at the end of each page. This causes the printer to
skip the perforation between pages of continuous forms. If zero
lines is specified, perforation skip will be disabled. If the
specified value is greater than or equal to the form length (as
defined in the Workbench preferences program), the skip
perforation is cancelled and the top and bottom margins become
inactive. The Perforation Skip is only enabled if Enable Form is
checkmarked.
Page Length
Paper Length is a read-only gadget showing the paper length as
defined in Workbench preferences. You can use the value as a
guide to setting your perforation skip and top margin values.
Changes made to the paper length preferences are automatically
detected by the StarPref program, and the gadget is updated
immediately without the need for exiting StarPref. The Paper
Length is only enabled if Enable Form is checkmarked.
Custom ResX
Custom ResY
If the selected paper format in preferences (Workbench 2.0:
"Printer") is CUSTOM, this option allows you to specify the width
of the printable area of paper in inch wide dots. The size is
used only for graphics dumps and does not affect text printouts.
For example, if you are using Workbench 1.3 (which doesn't have a
DIN A4 option) you can specify an X resolution of 2804 dots
(19.78cm, 7.8in), which is equal to the DIN A4 size used by most
Commodore printer drivers. If you specify zero (the default) as
the X resolution, the US-LETTER resolution of 2880 dots (20.3cm,
8in) will be used. The allowed range is 0 to 65535 dots.
Similar to Custom ResX, Custom ResY defines the height of the
printable paper size.
Use - Cancel
You can leave the window with the Use or Cancel gadget. Changes
made to the settings are accepted with Use. Cancel leaves the
settings unchanged and any changes made will be lost.
Note: Use does not save the changes made to your environment.
This is done by using the Use or Save gadget in the main window.
The Color Adjustments... window.
The gadgets in this window ebable you to make colour adjustments
and compensate for ink impurities. But why are colour adjustments
and ink compensation needed?
o Most colour printer users must have come across the problem of
graphics dumps being too dark, or the output containing too much
red. Using the colour adjustment you can easily correct this. As
default, the Star driver uses a gamma function to bright up
printings.
o The output quality of printers depends ultimately on the ribbon
and type of paper being used. Using the colour adjustment you can
easily alter the driver to various ribbon and paper types.
o The colour adjustment allows you to do image processing by
controlling the contrast, gamma correction and brightness of each
primary print colour. You can even filter out unwanted colours.
o Printer inks (or inks used in ribbons) are not completely pure
materials. For example there is some yellow mixed into the
magenta ink, and there is some magenta in the cyan ink. The ink
compensation values will correct for these impurities allowing
blues, for example, to be printed as blues rather than purples.
Colour adjustment is only one of several processes needed for
printing graphics. You can control the graphics output of the
Star drivers for each of these processes.
Before the printer driver can process a picture for printing it
must get separated into its primary printing colours. Each
primary printing colour can be adjusted by the Star printer driver
using 16 sliders which describe a conversion function. Colour
adjustment is needed because the colour values displayed on
computer monitor and the colours printed by printers are
different. A bright red on the monitor, for example, usually gets
printed as dark red; blue is often printed as violet; and the
printer output is often too dark.
Most printers cannot print two adjacent dots without overlapping
them slightly. This problem is known as `dot gain' Dot gain ,
causing muddy and dark output. You can avoid dot gain problems by
printing with a lower resolution (for instance 180 dpi on a 360
dpi printer) or by using a special dither matrix and colour
adjustment which is not affected by dot gain problems.
You can control the colour adjustment sliders in several ways.
There are three sliders in the upper right half of the Color
Adjustments... window. These provide global control over all 16
sliders that describe the conversion function.
Brightness
The brightness adjustment globally modifies the general brightness
of a colour component. It does this by uniformly shifting the
colour map upwards or downwards. All input intensities of one
primary printing colour will be shifted upwards (made brighter) by
the colour map. If you brighten all the primary printing colours,
the whole picture gets brighter.
The brightness adjustment is not without its drawbacks. Notice
that the darkest input value is brightened, leaving no darker
colours for printing. This means that the darkest intensity in
the image will also be brightened, which may not be acceptable.
Also note that most of the brighter levels now have exactly the
same intensity levels, meaning that all details which had
intensity levels in that range are lost.
The brightness control in StarPref ranges from to 50, with
zero being the neutral value. Setting the brightness control to a
positive value uniformly shifts the colour map upwards, towards a
brighter colour component. Similarly, a negative value causes the
colour to be shifted towards darkness.
Contrast
The contrast adjustment globally modifies the general contrast of
a colour component. Contrast adjustments can be visualized by
thinking of the neutral colour map being pivoted around its centre
point. At one extreme the colour map becomes flat, which means
that all input intensities map to the same output intensity (no
contrast). The other extreme is a vertical line for a colour map,
which produces a primary colour with exactly two intensities
(maximum contrast).
Notice again that contrast loses some amount of visual detail,
just as the brightness adjustment does. This may or may not be
acceptable for any given image.
The contrast control in StarPref ranges from to 50, with zero
being the neutral value. Setting the contrast control to a
positive value uniformly pivots the colour map around its centre
in an anti-clockwise direction (towards the vertical), which
increases visible contrast.
Gamma
The gamma adjustment provides a way to significantly brighten a
colour component without losing that much detail. It does this by
introducing a curve into the colour map, whereby the colour map is
shifted upwards or downwards (made brighter or darker
respectively) but no portion of the colour map gets clipped to the
maximum or minimum values.
The gamma adjustment also affects the contrast of the colour
component. In the darker part of the spectrum contrast is
increased; in the lighter part of the spectrum contrast is
decreased.
The gamma control in StarPref ranges from -50 to +50, where
zero represents no gamma adjustment.
The overall effect of gamma adjustment is usually quite
satisfactory and we recommend its liberal use. There are several
reasons for this. The gamma function provides an easy way to
brighten a picture without losing detail. Also, monitor tubes
show a computer picture using a non-linear conversion function,
and this function is very similar to the gamma function. Using
the gamma function allows you to more easily adapt the printer
output to the monitor picture.
Set
"Set" globally sets all 16 adjustment sliders of the active colour
component to the values defined by the Gamma, Brightness and
Contrast sliders.
Invert Bright+/- Default
Beside "Set" there are more gadgets providing global control over
the 16 adjustment sliders. Invert inverts all 16 sliders. The
two "Bright" gadgets allow you to increase or decrease the
brightness of all 16 sliders. "Default" resets all 16 sliders to
the default values wich is equal to a gamma correction of +32.
Adjustment sliders
The 16 colour adjustment sliders in the middle of the window give
you precise control over the colour adjustment function of the
driver. Each slider can be set to one of 256 shades. A higher
level means less of the currently selected primary colour. A
lower level means more colour, causing a darker picture. All 16
sliders describe a conversion function Conversion function . Dark
input values are adjusted by the sliders to the left, bright
colours are adjusted by the sliders to the right. As soon as you
click on one of the sliders, the value represented by the slider
is shown in the Level gadget on the left-hand side of the window.
Colour pictures are printed by most printers using three or four
primary colours. Usually these colours are cyan, magenta, yellow
and black. (Black is not used by DeskDriver). All 16 colour
adjustment sliders are applied to one primary colour. You can
choose which primary colour to adjust using the Color cycle gadget
in the upper left-hand corner of the window.
But what if you want to use the gamma function to brighten a
greyscale picture? For this purpose select B/W-Grey as the colour
and use the gamma slider to select the required gamma setting.
Apply the gamma setting to the 16 adjustment sliders by clicking
on the "Set" gadget. After leaving the StarPref program using
"Use" or "Save", the gamma function is active.
While each of the 16 colour sliders provides 256 levels, this does
not necessarily mean you can print 256 shades of each colour. The
number of colours or shades printed depends upon the number of
colours or shades supported by the dither matrix being used. The
Star installation program installs an Ordered-A dither method with
64 shades as the default dither routine. More information about
setting up a dither matrix can be found on in a chapter below.
Push Pop
Now, say you want to apply a specific gamma function to each
primary colour. Sure, you could use the same technique for
installing the gamma function as described in the example above
for every primary colour. But this technique can be a real pain
if you have adjusted some sliders by hand. This is why the Push
and Pop gadgets got introduced. Push saves all your current
slider settings on to the stack. After changing the colour
component you can easily Pop the settings from the stack. Using
Pop for every colour component is fast and easy.
Load Save
You can save the your colour adjustment function to a file for
later use. You could save your adjustment settings for various
kind of paper types, for example, and reload them when needed.
Save will cause the system file requester to appear and you can
choose a path and filename for saving. Load will cause the file
requester to appear and you can choose the file for loading. Note
that Save and Load only affect the currently selected colour
component.
Comp M Comp Y
The integer gadgets Comp. M and Comp. Y can be used to adjust
the ink compensation of the printer driver. Printer inks used in
ribbons are not completely pure materials. For example there is
some yellow mixed into the magenta ink, and there is some magenta
found in the cyan ink. The ink compensation values will correct
for these impurities allowing blues, for example, to be printed as
blues rather than purples.
Comp. M defines the percentage of magenta ink in the cyan ink.
Comp. Y defines the percentage of yellow ink in the magenta ink.
Star's custom dither and colour correction routines can be turned
off by printing with a Workbench dither method other than
"ordered", or a density below 3. Because of this, colour
adjustment and ink compensation work only with the ordered dither
routine set in Workbench preferences and densities above 2.
Colour adjustment works with nearly every Amiga application.
Application programs with their own colour adjustment routines
should not be used with Star's routines enabled. Programs with
their own colour adjustment routines include Art Department
Professional's PrefPrinter saver, TruePrint24 and PageStream. Use
density 1 or 2 when printing with these programs. The Studio
picture-printing program also belongs to this category of
programs, but it automatically disables the Star driver's colour
adjustment routines.
Use Cancel
You can leave the window with the Use or Cancel gadget. Changes
made to the settings are accepted with "Use". Cancel leaves the
settings unchanged and any changes made will be lost.
Note: Use does not save the changes made to your environment.
This is achieved by using the Use or Save gadget in the main
window.
Customize Dither... Dither Routines
Most printers print pictures using a `binary coding', or to put it
more simply: a dot can either be printed, or not. There is no
way to control the brightness of a single dot. A monochrome
printer can only print one colour: black. Colour printers
support the printing of three or four primary colours: cyan,
magenta, yellow and black.
A special technique is needed for printing more shades. Dither
routines provide such a technique. Dither routines print dots of
a primary colour in various patterns, creating the impression of
different shades, thanks to the fact that the human eye can't
distinguish adjacent dots from a distance.
Each pixel of a picture produces a pattern of printed dots. The
pattern is described by a dither matrix. There are almost no
limits to the size of the dither matrix. Workbench dither
matrices (ordered and halftone) are of the size , which is equal
to printing shades A normal matrix produces 17 shades. This is
not true in case of the Workbench dither matrix. . A matrix
consists of threshold values. Each matrix value is compared with
the picture's pixel value. If the value of the pixel is higher
than the matrix value, a dot gets printed.
Dither patterns allow you to print a huge number of shades. The
number of printable shades mainly depends on the size of the
dither matrix used and the quality of the printer.
Many printers have problems with overlapping dots. These problems
have a huge influence on the decision as to which dither matrix to
use. There is also a strong relationship between a dither matrix
and the colour adjustment required. A change of print density
often requires a change of the dither matrix and/or colour
adjustment, and changing the dither matrix usually requires the
colour adjustment also to be changed.
StarPref gives you the facilities to define the dither matrix used
for printing. Many dither matrices are included with the Star
driver. These are handled in an extra below chapter; this chapter
covers only the use of the Customize Dither... window. This
window allows you to edit the current dither pattern. Instead of
editing a pattern, you may quickly load a pattern using the window
shown after selecting "Customize Dither...".
The theoretical aspects of digital halftoning are complex, and are
way beyond the scope of this manual. If you are interested in
more detailed information, a very good book can be recommended:
Robert Ulichney
Digital Halftoning
MIT Press
ISBN 0-262-21009-6
The book is easy to understand and comes with lots of examples.
Most of the dither routines used by the Star software are
described in detail in this book.
Load Save
Using the Customize Dither... window is very similar to using the
Color Adjustments... window. The Load and Save gadgets allow you
to load and save the required dither matrix for a particular
colour component. Only the currently selected Color component is
saved or loaded.
Push Pop
Let's assume you want to print a colour picture using the halftone
dither. There are two ways you can enable the halftone dither in
StarPref. You can either load the dither matrix from disk for
each primary colour, or you can use the stack. The stack can be
controlled using the Push and Pop gadgets on the left-hand side of
the window.
All you have to do to install the required dither matrix is to
load the dither. Afterwards click on the Push gadget and the
dither is saved on to the stack. Now switch the primary colour
and Pop the matrix from the stack. Enable the matrix for all
primary colours by using the stack. You can switch between the
primary colours by using the Color cycle gadget Color .
A Star dither matrix may be any rectangular shape and can consist
of up to 512 values. Up to 64 values can be included on each row
(X) or column (Y). You can use the X and Y sliders to define the
size of the matrix. The current size of the matrix is shown on
the left-hand side of the window.
Star's custom dither routines can be turned off by printing with a
Workbench dither method other than ordered , or a density below 3.
The custom dither routines works with nearly every Amiga
application. Application programs that provide their own dither
routines should not be used with Star's routines enabled.
Programs that do not work include Art Department Professional's
PrefPrinter saver, TruePrint24 and PageStream. Use density 1 or 2
when printing with these programs. The Studio picture-printing
program also belongs to this category of programs, but it
automatically disables the Star driver's dither routines.
Dither Routines
Many dithering methods are supplied with this driver, and these
are described below. In each case a larger dither mask size
produces a printout which can represent a wider range of colours,
but will produce less spatial information per unit area of paper.
Conversely, a smaller dither mask size can reproduce fewer colours
(or shades) but more closely approximates the true resolution of
your printer.
Another way of expressing this is simply that there is a tradeoff
between printing ``lots'' of colours and printing in high
resolution. Given a specific printer with a specific DPI
capability, asking for ``lots'' of colours means using a larger
dither mask size. A larger dither mask size cuts down on your
effective resolution. For instance, using a dither mask of 16*16
on your 360 dpi printer will result in 360 / 16 = 22,5 dpi This
values is often described as l/inch (lines per inch) or `screen
frequency'. with full colour information.
Note that this can work to your advantage when enlarging a
picture. Enlarging means that there are more dots to work with,
which offsets the loss in resolution caused by a larger dither
mask size. This, added to the benefits to be had by being able to
reproduce more colours (or shades).
Also note that many printers, including most laser printers and
dot-matrix printers, have considerable dot gain problems. For
example, a 360 dpi printer does not actually print dots which are
of an inch in size. Rather, its dots will be much larger. This
causes some dithers, such as the Ordered dithers, to produce
intensely over-saturated or `muddy' prints. Other dithers, such
as the two halftone dithers, overcome this problem with low-end
printers.
If you want to learn more about dither routines and digital
halftoning, here is a very good book to go for:
Robert Ulichney
Digital Halftoning
MIT Press
ISBN 0-262-21009-6
The book is easy to understand and comes with lots of examples.
Most of the dither routines used by the Star driver are described
in detail in this book.
See the description of the "Customize Dither..." window for
information on how to enable a required dither routine for a
Star printer driver.
OK, now let's discuss the dither routines in detail:
While using the StarPref program, click on the button marked
"Customize Dither..." for using one of the dithers described below.
Several popular ordered dither methods are provided with StarPref.
These can be loaded and enabled with the listview shown after
clicking on Customize Dither... .
The number of printable colours is usually directly related to the
size of the dither matrix. Most of the ordered dither routines
described below exist in several sizes. You can distinguish
between them by their filenames. For instance a filename of
"Halftone-A-4" means the Halftone A dither routine for 4 shades;
while "Halftone-A-256" means the Halftone A dither routine for 256
shades.
Halftone-A - number of colors
Halftone-B - number of colors
10 Percent 20 Percent 50 Percent 80 Percent 90 Percent
**** ******** ********
* *** **** ***** ** *****
** *** **** ***** * *****
**** ******** ********
**** ******** ********
** *** **** **** * ****** *
** *** **** **** * ***** *
* **** ******** ********
The halftone dithers (Halftone-A and Halftone-B) differ in how
they place a halftone matrix.
This is the classic clustered halftone method used by most book
publishers, and PostScript. To improve the dither output the
halftone matrix is rotated by 45 degrees. Halftone-A causes the
halftone matrix for each of the primary colours to be centred
about the same point. This means that the primary colours will
overlap completely, leaving a lot of white paper showing through.
This may be appropriate for some better dye-sublimation type
printers, or other colour printers with good registration where
the inks mix well.
Halftone-B, on the other hand, staggers the halftone matrix of
each primary colour so that they do not overlap. This is similar
in concept to traditional colour offset printing. Halftone-B may
produce better results on printers whose inks do not mix well, and
on printers with less than perfect registration.
The halftone dithers can produce some extremely good results and
compensate for the dot gain problems outlined above. Try both
halftone dithers to see which one is better for your particular
intention. If you are going to photocopy your printouts, using
Halftone results in a much better copy.
Halftone-B is somewhat different to the other dither matrices.
You have a special dither matrix for each colour. Because of
this, each dither filename includes the abbreviation of the color
(C = cyan, Y = yellow, M = magenta, K = black or greyscale).
If you are using Halftone-B with one of the Star printer drivers,
you must increase the brightness of the black colour component by
50%. Use the bright+ gadget in the StarPref preferences programs
for increasing brightness.
Halftone-B is a good example of the relationship between colour
adjustment and dither routines. You have to consider both
settings.
PrtDevice-Halftone-16
10% 20% 30% 40% 50% 60% 70% 80% 90%
* * * * * * * * * * * ** * ****
* * ** ** ** *** **** **** ****
* ** ** ** ** ** ** ****
* * * * * * * ** **** **** ****
PrtDevice-Ordered-16
10% 20% 30% 40% 50% 60% 70% 80% 90%
* * * * * * * * * *** **** **** ****
* * * * * * * * * ** * ****
* * * * * * * * * * ** **** **** ****
* * * * * * * * * ****
This dither matrix is the one used by the Workbench printer
devices Halftone or Ordered dither.
The dispersed ordered dither produces a regular repeating pattern
which is often used for printing computer graphics. The ordered
dither is particularly vulnerable to over-saturation due to dot
gain in high resolutions. But you will get good output if you
don't use the maximum print density of your printer (for instance,
by using 180 dpi on a 360 dpi printer).
Ordered-A-Dither
10 Percent 20 Percent 50 Percent 80 Percent 90 Percent
* * * * * * * * * * * * * * ******
* * * * ******** ********
* * * * * * * * * * *** *** *** ***
* * * * ******** ********
* * * * * * * * * * * * ***** **
* * * * ******** ********
* * * * * * * * * *** *** *** ***
* * * * ******** ********
The dispersed ordered dither produces a regular repeating pattern
which is often used for printing computer graphics. The ordered
dither is particularly vulnerable to over-saturation due to dot
gain in high resolutions. But you will get good output if you
don't use the maximum print density of your printer (for instance,
by using 180 dpi on a 360 dpi printer).
Ordered-B-Dither
10 Percent 20 Percent 50 Percent 80 Percent 90 Percent
* ** ** ** ** ******** ********
** ** ** ** ** ******** ********
** ** ** ** ***** **
** ** ** ** **** ***
** * ** ** ** ******** ********
** ** ** ** ******** ********
** ** ****** ******
** ** ****** ******
This dither is a mixture of a dispersed dither like Ordered and a
clustered dither like Halftone. The dither is meant specially for
high resolution printers with dot gain problems. For instance, if
you print a picture with 360*360 dpi using Ordered-B-64, you get a
picture that appears to be printed at 180*180 dpi. But while
colours are printed emulating 180*180 dpi, all the black parts of
the picture are printed using 360*360 dpi. Don't get confused,
the printed picture is still better than a picture in real 180*180
dpi resolution. The Ordered-B dither is especially useful for
colour DTP because you can combine good colour pictures with fine
high quality text.
Spiral-Dot-Screen - number of colors
10 Percent 20 Percent 50 Percent 80 Percent 90 Percent
******** ********
****** ******** ********
* **** ****** ******** ********
*** **** ****** ******* ********
*** **** ****** ******* ********
* ****** ******* ********
** ******* ********
**
A wide range of special effects clustered-dither matrices are
available in the graphic arts industry, and all are easily
simulated digitally. Spiral-Dot is such a dither.
The spiral-dot dither is essentially half of the classical
`screen', with dark squares growing to fill the plane without the
alternating light squares. Spiral-Dot looks quiet similar to the
Halftone-A matrix, zero degree rotated.
Horizontal - number of colors
Vertical - number of colors
10 Percent 20 Percent 50 Percent 80 Percent 90 Percent
******* *********
***** ********* *********
**** ********* ********* *********
******* ********* ********* ********* *********
********* ********* *********
********* *********
****
A wide range of special effects clustered-dither matrices are
available in the graphic arts industry, and all are easily
simulated digitally. The Line dithers are such dithers.
The horizontal (as well as the vertical) dither overcomes many of
the dot gain problems that the Ordered dithers have with low-end
printers. These dithers (particularly the diagonal dithers) are
especially good for large pictures.
Fwd-Brick- number of colors
Bck-Brick- number of colors
10 Percent 20 Percent 50 Percent 80 Percent 90 Percent
** *** ***** ******* ********
* ** **** ****** * ****** *
* *** * **** ** ***** **
** ** *** *** **** ***
* ** ** **** *** ****
* *** * ***** ** *****
* ** **** ****** * ******
** *** ***** ******* *******
A wide range of special effects clustered dither matrices are
available in the graphic arts industry and all are easily
simulated digitally. The Brick dithers are such dithers.
The Forward-Brick (as well as the Backward-Brick) dither overcomes
many of the dot gain problems that the error diffusion, Blue Noise
and Ordered dithers have with inexpensive printers. These dithers
are especially good for enlarged pictures.
Floyd Steinberg (no "char" picture)
This is a very popular error diffusion dither method first
suggested by Floyd and Steinberg. They argued that a filter with
four elements was the smallest number that could produce `good'
results. The values were chosen to particularly ensure a
checkerboard pattern at the middle grey or shade of colour. This
dither method provides a good compromise of speed and quality.
The reason for the popularity of this algorithm is clear --
several colour shade levels are represented by pleasingly
isotropic, structureless distributions of dots. But there are
some shortcomings:
* Correlated artifacts in many of the colour shade level patterns.
This can be easily seen by printing a greyscale ramp.
* Directional hysteresis due to the raster order of processing.
This artifact is most apparent in very light and very dark
patterns.
* Transient behaviour near edges or boundaries.
Jarvis, Judice und Ninke
In 1976 Jarvis, Judice and Ninke documented an error filter with
12 elements. The large filter size reduces some of the artifacts
seen with the 4-element filter of Floyd and Steinberg, but
directional hysteresis in the very dark and light regions are
increased, and pixels are clustered together more in the middle of
colour shade regions. It also sharpens the pictures.
Stucki-Dither
The Stucki filter provides nearly the same output as the Jarvis
filter, though you may notice differences in sharpness.
Blue-Noise 30-50%
In trying several combinations of deterministic values in a
4-element error filter, none proved better than the famed filter
of Floyd and Steinberg. Two variations of this basic filter are
the Blue Noise dithers. Both are processed with serpentine
rasters. The serpentine raster used in processing is responsible
for much of the directional artifact elimination. The noisy
threshold (30% or 50% white noise) breaks up most of the remaining
stable texture patterns, yielding good radial symmetry at the
expense of adding some low frequency energy.
Blue noise is especially useful when printing light shades and
fading colours.
All error diffusion dithers, including Blue Noise, can produce
very good results on colour printers that have little dot gain and
very good registration. If it produces a washed-out print or
particularly bad patterns, then try another dither (see the custom
Ordered-B or Halftone, for instance).
Errors & Fixes
==============
For those who deal with computers and printers, it's a known fact:
Everything possible that can go wrong, will go wrong. Especially
when it comes to printing, there are many places were you can make
mistakes.
If you find a problem with a printer driver, please send a
description which makes it possible to reproduce the problem. For
this purpose, you should provide following information:
o Which application program are you using, and which version of it?
o Which Workbench revision are you using?
o Include a dump of the program, as a file (use the CMD program
from the Workbench disk for this) and in printed form.
o If possible, provide a copy your Workbench disk or application,
already set up for printing.
o provide a dump of the "Report" program enclosed on all Star
driver disks. You can get a dump by typing following lines in
the Shell:
"Star-Drivers:report >ram:dumpfile"
"copy ram:dumpfile par:"
Installation program fails
Often, an error reported by the installation program is caused by
full system disks. Please make sure there is enough free disk
space available. 65KBytes free space is really save for
installing the driver - not the StarPref program (wich requires
~90 KBytes and can be installed on any free disk)
Par: or Prt:?
Data should be sent to the printer only via parallel.device (par:)
or printer.device (prt:), and not both at the same time as this
may confuse the printer.
No dump?
If the printer device immediately reports an error while trying to
print a graphic, check that you have selected the Star printer
driver in Workbench preferences.
No way for Kickstart 2&3?
Your printer doesn't work under Kickstart 2 or 3, while with
Kickstart 1.3 it works fine? Check the "on-line" and "out of
paper" lines in the printer cable. Make sure they are connected
correctly. If your cable is wired right, check the two Amiga port
chips named 8520. There have been major changes in Kickstart 2
regarding the use of the port chips. Ask your dealer for help if
these tips are too technical for you!
Empty pages?
Empty pages is a known problem of Amiga printer drivers. After
graphics dumps an empty page is printed. So far there is no 100%
cure for this problem. Some application programs don't cause an
empty page if you enable the Continuous paper type in preferences.
Printer trouble... ?
Printer trouble... requester? Have a look at the TimeOut setting
of the StarPref program. Setting a longer Timeout can avoid such
requesters. Anyway, clicking on the Resume button continues
printing without loss of data.
No Formfeed?
If a page is not ejected, check your paper type preferences. Make
sure Single is selected as the paper type. Deluxe Paint users may
run into the problem of an endless graphic dump -- the Deluxe
Paint print requester won't disappear, and the printer doesn't
eject the page. This is a known bug in Deluxe Paint and can be
easily cured by a mouse click in the Deluxe Paint print requester.
Differences between KS 2 and KS 1.3?
After switching from Workbench 1.3 to 2/3 your graphic dumps are
of different size? This most likely will happen to users using
the DIN A4 paper size. For instance, under Workbench 1.3 you used
the Letter size, and after switching to Workbench 2/3 you used the
DIN A4 size. Because the Star driver supports the new paper sizes
(DIN A4, A5 ...), you get a different printout under Workbench
2.0/2.1. Simply switch back to the Letter size to get the same
result as under Workbench 1.3.
Patching drivers
There are several programs that allow you to `patch' printer
drivers in order to alter specific commands or parameters like the
Timeout value. Do not use these programs!
To dark pictures?
If your graphic dumps are too dark or wrongly coloured, it is most
likely caused by the disabled colour adjustment routines of the
Star driver.
Environment Vars
If you have never heard of `environment variables', this chapter
is not for you. But don't panic, you won't be missing anything
unless you are still using Workbench 1.3.
So this chapter is mainly of interest to experienced users. It
covers controlling the driver from ARexx, Shell or batch files.
You may set options for the Star driver by using the setenv and
getenv Shell commands instead of the StarPref preferences program.
Setenv saves your option in a file in the ENV: directory. See
your system manual for a complete description of the setenv and
getenv commands. The driver will read in the arguments upon
opening the printer device. If you don't have enough memory, the
driver refuses to open.
Note: setting options does not always mean they take effect
immediately. So if you make changes by using setenv , flush the
driver out of memory (AVAIL FLUSH) or run InitPrinter in order to
let the driver know about your changes. The StarPref
preferences programs will do this for you automatically.
Remember that environment variables (which are stored in the ENV:
directory) are normally erased by re-booting. If you don't want
to set the environment variables every time you boot, you can
place them in ENVARC: (Workbench 2/3) or assign ENV: to a non
volatile disk (Workbench 1.3). Make sure you use the Commodore
setenv command to set environment variables. Environment variable
names are not case sensitive.
OK, now a description of every environment variable in detail:
sbox_printer 0|1|2|3 (default: 0)
The driver supports the arXon parallel switch-box, an external 1
to 3 Centronics switch controllable by software. You can ask the
printer driver to automatically switch to the required port for
printing, and switch back to the previously used port after
printing. This enables you to use a scanner, a digitizer and a
printer from your Amiga's parallel port without having to switch
between the devices manually. If you specify Default as the port,
no switching will take place.
Information about the arXon switch-box may be obtained from:
arXon GmbH
Assenheimer Str. 17
D-60489 Frankfurt
Germany
Tel: 010-49-69-7896891
Fax: 010-49-69-7896878
The environment variable sbox active must be specified before
using the driver in order to enable the switch-box feature of the
driver. This is because sbox active is used to determine whether
a switch-box is installed or not. sbox_active is defined by the
arXon software.
StarGAdj: <Num1-16>
StarCAdj: <Num1-16>
StarMAdj: <Num1-16>
StarYAdj: <Num1-16>
StarKAdj: <Num1-16>
(default: 0 90 117 137 153 167 179 190 200 210 218 226 234 241 248 255)
You may define a colour adjustment function using 16 values for
each primary print colour (G=grey, C=cyan, M=magenta, Y=yellow and
K=black). Each of the 16 values must be in the range 0 (black) to
255 (white). The brightness of the input values increases from
left to right (0 to 255).
StarBeep: 0|1|2|3 (default: 0)
If the printer device gets closed after a dump, you can tell the
driver to signal the end of the print job. This is especially
useful with huge graphic dumps which might require some time.
There are two kinds of signals. You can cause a beep (Ctrl-G) on
the printer, a DisplayBeep on the Amiga, or both:
0 = No signal (default)
1 = Beep
2 = Flash
3 = Beep Flash
StarColor <Num> (default: 0)
StarColor defines the default text printing colour:
0 = Black (default)
1 = Magenta
2 = Cyan
3 = Blue
4 = Yellow
5 = Red
6 = Green
StarGDit: <X> <Y> <a11, a12,... etc.> (default: Halftone A 64)
StarCDit: <X> <Y> <a11, a12,... etc.> (default: Halftone A 64)
StarMDit: <X> <Y> <a11, a12,... etc.> (default: Halftone A 64)
StarYDit: <X> <Y> <a11, a12,... etc.> (default: Halftone A 64)
StarKDit: <X> <Y> <a11, a12,... etc.> (default: Halftone A 64)
These variables allow you to define the required dither matrix for
each primary print colour (G=grey, C=cyan, M=magenta, Y=yellow and
K=black). Several dither matrices are included with StarPref
(Ordered, Halftone, Spiral, Line, etc.). These matrices are
stored in a directory named ` dither-settings ' which can be found
in your ` Dither-Settings ' drawer. You may copy these matrices
directly to env: , or define a matrix of your own.
SetEnv StarEmu 0|1|2 (normal: 0)
Defines graphic emulation:
Star SJ144 driver:
0 = Epson 48 (default)
1 = CDM
Star24Plus driver:
0 = Epson 24 (default)
1 = Epson 48
2 = Star 48
SetEnv StarCDitAlg 0|1|2|3|4|5 (normal: 0)
Defines color dither algorithem.
0 = Order Algorithem as defined in Star(C|M|Y|K)Dit
1 = Floyd Steinberg
2 = Jarvis
3 = Stucki
4 = Blue Noise 30% Random
5 = Blue Noise 50% Random
SetEnv StarGDitAlg 0|1|2|3|4|5 (normal: 0)
Defines greyscale dither algorithem:
0 = Order Algorithem as defined in StarGDit
1 = Floyd Steinberg
2 = Jarvis
3 = Stucki
4 = Blue Noise 30% Random
5 = Blue Noise 50% Random
StarTop <Num> (default: 0)
Number of lines for the top border.
StarGFeed <Num> (default: 0)
Most printers have problems with their internal mechanics causing
unwanted horizontal stripes in the graphic output. Often the
linefeed is a bit too much or too little, causing dark or white
horizontal lines. This problem is called `banding'. StarGFeed
allows you to adjust the driver to the mechanical inaccuracy of
the printer. Set StarGFeed to 1 if you have white lines in the
output, or 2 if you have dark lines:
0 = Normal linefeed
1 = Decrease linefeed
2 = Increase linefeed
StarForm ON|OFF (default: OFF)
If StarForm is ON , page length (as set in Workbench preferences)
and Perforation Skip will be enabled by the driver. In order to
stay compatible with normal Workbench printer drivers, by default
the settings are not used. Some applications require a
well-defined paper size and margins for printing forms. The Star
driver provides you with these facilities by setting StarForm to
ON . It may require some experimentation (and paper) until you
find the correct values for a specific application.
StarMagenta: <Num> (default: 0%)
Printer ribbon inks are not completely pure materials. For
example there is some yellow mixed into the magenta ink, and some
magenta in the cyan ink. The ink compensation values will correct
for these impurities. With magenta compensation you specify the
percentage of magenta in the cyan ink.
The ink compensation function can be completely disabled by
specifying 0 . You will notice that without the ink compensation
function a blue sky will print as purple. With the ink
compensation function set to 10--30 , blue skies are usually blue
again.
StarMagenta defines the percentage of magenta in the cyan ink,
and may range from 0 to 100%.
StarMirror: ON|OFF (default: OFF)
If set to ON , graphics will be mirrored. Especially useful if
you want to print pictures intended for T-shirt art.
StarPerf: <Num> (default: 0 lines)
If StarForm is set to ON, StarPerf specifies the number
of lines that the printer skips at the end of each page. This
causes the printer to skip the perforation between pages of
continuous forms. If zero lines are specified, perforation skip
will be disabled. If the specified StarPerf value is greater
than or equal to the form length (as defined in the Workbench
preferences program), the skip perforation is cancelled and the
top and bottom margins become inactive.
StarResX: <Num> (default: 0 dots)
If the preferences paper size is CUSTOM , this option allows you
to specify the horizontal resolution (width) for graphic dumps.
The size is specified in 360 dpi dots. If you specify zero (the
default) as the resolution, the US LETTER resolution of 2880 dots
will be used. The allowed range for <Num> is 0 to 65535 dots.
The StarResX setting is used by the driver for graphics
printing only.
StarResY: <Num> (default: 0 dots)
If the preferences paper size is CUSTOM, this option allows you to
specify the vertical resolution (height) for graphic dumps. The
size is defined as 360 dpi dots. If you specify zero (the
default) as the resolution, the US LETTER resolution will be used.
The allowed range for <Num> is 0 to 65535 dots. The StarResY
setting is used by the driver for graphics printing only.
StarSep: C M Y K (default: CMYK)
With this option you can print a CYMK colour component of a
picture. For example, if you want to print the cyan component of
a picture set StarSep to C . The combination of following
characters, in any order, is allowed:
C = Cyan
M = Magenta
Y = Yellow
K = Black
StarSuper: ON|OFF (default: OFF)
Normal Workbench printer drivers are limited to 16 shades of grey.
After brightening the graphic output, even fewer shades are
available. Star drivers do not have this limitation and can print
colour pictures in up to 256 shades of grey.
With StarSuper enabled, every colour picture will be printed as a
greyscale picture if you select colour instead of greyscale as the
graphics output mode. With Supergrey it is the printer driver's
task to convert the colour data into greyscale data. While this
can be done by the printer device instead of the printer driver
(as normal Workbench drivers do), the Star printer driver
colour-to-greyscale conversion routines are more precise. Because
of this you can print a 4096 colour HAM picture in up to 256
shades of grey instead of the normal 16. Supergrey will replace
the normal colour dump of the driver.
The Table below shows all parameters that must be enabled for
printing with Supergrey.
Function Density Workbench dither
Supergrey >2 ordered
Colour Adjustment >2 ordered
Ink compensation >2 ordered
Driver dithers >2 ordered
Note: the number of printable shades of greys in Supergrey
depends on the number of shades supported by the dither method set
in StarPref. Up to 256 shades are possible, and supported by the
Star dither routines. Often a dither method that produces 64
shades (default) gives best results.
StarTab: <Num> (default: 9, 17, 25,...)
This environment variable allows you to customize the horizontal
tab stops settings of your printer. This may be useful for
printing program listings and tables. Up to 32 tab stops may be
defined.
StarTime: <Num> (default: 60 seconds)
If huge amounts of data are being transferred to the printer, the
actual printing of the image happens much faster than the transfer
of the data. A requester may appear on the screen saying `
Printer trouble... '. This appears because the printer device
thinks no data has been transferred due to a hardware or software
failure. With StarTime you can specify the time that should
pass before the printer device puts up the error requester.
With Timeout you can specify a higher timeout value, resulting in
fewer timeout requesters. A value from 1 to 999 seconds is
allowed (default 60 seconds).
Instead of defining a huge timeout value there is another solution
available: use the CMD program (see your Workbench disk) to
redirect the parallel/serial output to a file on disk. After
this, use the Copy command or a printer spooler to copy the file
to par: .
Note: if a real error occurs, you will have to wait the number of
seconds specified by StarTime until an error requester
appears, thus allowing you to cancel the print job. So choose
your StarTime value wisely.
StarType: <Num> (default: 0)
Specifies the typeface to be selected on aRIS, aRIN and aFNT0. If
you select zero (the default), the typeface selected on the
printer control panel will be used. StarType may range from 0
to 255. See your printer manual for the values used for selecting
a required typeface on your printer, and add 1 to the value.
StarYellow: <Num> (default: 0%)
Printer ribbon inks are not completely pure materials. For
example there is some yellow mixed into the magenta ink, and some
magenta in the cyan ink. The ink compensation values will correct
for these impurities. With magenta compensation you specify the
percentage of magenta in the cyan ink.
The ink compensation function can be completely disabled by
specifying 0%. You will notice that without the ink compensation
function a blue sky will print as purple. With the ink
compensation function set to 10-30%, blue skies are usually blue
again.
StarYellow defines the percentage of yellow in the magenta ink
and may range from 0 to 100%.
Glossary
========
Default
A value used in place of a user-selected value. A factory default
is a value programmed into the device at the factory; this value
is stored in read-only memory (ROM) and cannot be changed by a
user or operator. A user default is a default that is selectable
via the control panel.
Dot
A dot is the smallest thing a printer can print. The number of
dots printed per inch is referred to as the printer's resolution
(dpi).
Download
The process of transferring soft fonts, macros or raster data from
a host computer to the printer's user memory is called
downloading.
DPI
See Dot.
ENV: ENVARC:
The Amiga operating system and the Star drivers stores their
environment settings in two special directories named ENV: and
ENVARC:. Settings saved in ENV: are only for temporary usage and
get lost when turning the computer off.
Parallel I/O
An input/output interface that transmits more than one bit of
information simultaneously. Centronics is an industry-wide
standard form of a parallel interface.
Pitch
Pitch describes the number of characters printed in a horizontal
inch. Pitch only applies to fixed-spaced fonts since the number
of characters per inch varies for proportionally-spaced fonts.
See Spacing.
Printable Area
The printable area is the area of the physical page on which the
printer is able to place a dot, wheras the physical page refers to
the actual size of the paper installed in the printer.
Raster Graphics
Images composed of groups of dots are called raster images.
Spacing
Fonts have either fixed or proportional spacing. Fixed-spaced
fonts are those for which the inter-character spacing is constant.
Proportionally-spaced fonts are those for which the
inter-character spacing varies with the natural shape of a
character.
Typeface
Typeface is a generic name for graphics symbols having common
design features. Each typeface has unique and distinguishing
characteristics.