Spectrofon #09 30 сентября 1994

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System - details the work with your printer. Article Starter users and programmers.

           SYSTEM


  SERGEY Savoshchenko.


   Performer for "ZX-SPECTRUM".

   -------------------------

            INTRODUCTION


   Printer - a peripheral
device, which want to have
before most
users "ZX-SPECTRUM".


   Immediately, we note that this
Computer literacy can connect virtually any printer, but
This may occur one or
other difficulties. Joint efforts
we will try to overcome these
difficulties.


        Interface type.


   This point is very
important because depends on it
way to connect the printer to
computer.


   There are two main methods of information exchange between
computers and periferynymi
devices - Parallel and
serial.


   In parallel connection
all the bits that make up the bytes parcels are sent at the 
same time on parallel data buses.



   When a sequence of bytes transmitted bit by bit at a time.



   Historically, over interfaces
implementing a parallel method
transmission stuck title
"CENTRONICS", but for consistent - "RS 232".

METHODS OF INTERFACE.


   For "SPECTRUMa" there
Several ways of organizing
interfaces for connecting
printer. We consider the two most popular ways to organize:

1. Realization using chips KR580VV55A;

2. Interface ZX-PRINT (MK III).



     INTERFACE KR580VV55A.


   To implement an interface type "CENTRONICS" useful 
KR580VV55A chip, which is a programmable interface adapter 
(PIA). The structure consists of three PIA 8-bit parallel I / O 
ports A, B, C. In our In the scheme of the port used for

output data DATA 0-7 on
printer, the LSB
Port C - RS0 transmitted signal
GATE, a senior level - RS7
to enter a busy signal
printer. Port A is reserved
a joystick. The program interface support inserts in the 
control register PIA number 136, which corresponds to the 
setting PIA in output mode for port B and 4-m

LSB port, and enter the 4 th highest-Port S.

   Note that after switching
supply or after resetting all
PIA ports configured in Mode
input. In addition,
Addressing port A is chosen such that it allows the use of
it as an interface
joystick. The joystick will be chosen at zero on the tires A5
, RD, IORQ, which corresponds to the address Kempston interface.


   The printer is connected to the interface with the cable 
length 1,5-2m.



   To increase the load
the ability to output interface
You can include a buffer element
in which we can use any TTL chips
without inversion, eg
155LP4, 155LP10, 155LP11, 555AP5,
555AP6, 589AP16 etc.

    Some printers use a parallel interface
IRPR different from CENTRONICS
as the polarity of the signals, and
exchange protocol.


    Despite the differences in communication protocols, circuit 
and program support interface CENTRONICS

may well work with printers equipped with the interface
IRPR. To do this, invert the information line
DATA 0-7 and buffer the signal
SC, as in IRPR required currents
load of about 40mA. Signal AC
is used instead of a busy signal and the signal SC instead of 
the signal GATE. As inverters and

buffers can be used chip "XOR" - 155LP5.
In this case, feeding on the second
inputs of the elements chips "1"
or "0", you get the output
inverted or non-inverted signal, so your
Parallel to
universal.


      ZX LPRINT (MK III).


   Your attention is invited
description of the next interface model: ZX-LPRINT (MK III). 
This interface can be configured and

support equipment as a
"CENTRONICS", and with the RS232.


   Mk III - printer interface
can be used with version
16K, 48K and 128 K and different
Other brand and amateur
ZX-SPECTRUM for printing messages, graphics and text
printers that use parallel (type CENTRONICS) or
serial (such as RS232-5v)
interfaces.

   When power
ZX-SPECTRUM beyond the normal
Input Menu (Intro), while
All functions are preserved.



         Initialization.


   After switching on the Mk III has
be initialized by the command
"Carriage return" (CARRIGE
RETURN (CHR $ 13). This is a team of "LPRINT + ENTER"
or "LPRINT + line" in the program for
BASIC. During initialization, Mk
III automatically goes to the regime to print the text (TEXT 
MODE) and sets the printer to print

80 characters per line.



   The choice of different types of graphics printers by
following commands:

LPRINT CHR $ 0; CHR $ 0 - Call
"MENU"

LPRINT CHR $ 0; CHR $ 1 - SEIKOSHA
GP 250 X

LPRINT CHR $ 0; CHR $ 2 - SEIKOSHA
GP 100 A
LPRINT CHR $ 0; CHR $ 3 - EPSON
(Models with high resolution)
START DP 510, GEMENI I STX 80

LPRINT CHR $ 0; CHR $ 4 - WALTERS
WM80, SHINWA and CTI CP 1980

LPRINT CHR $ 0; CHR $ 5 - for
CHR $ 3, but the copy is reduced



LPRINT CHR $ 0; CHR $ 6 -
MIKROLINE 80 and 82, or the like
CG115 and 'MCP40 in 4 colors


   Selectable command is displayed on the bottom line.
Bust by pressing
"SPACE" (SPACE). Confirmation
selection by pressing
"ENTER".


      Interface commands.

LPRINT CHR $ 3 - carriage return
with a linefeed (CR + LF)

LPRINT CHR $ 2 - only to return
carriage

LPRINT CHR $ 1; "A" - where "A" can be from 1 to 8. This tells
machine how many digits after the command will be interpreted
as printer commands
LPRINT CHR $ 4 - just one sign of
interpreted as a command
Printer

LPRINT CHR $ 5 - decoder
machine is turned off, that is all
plates issued by this command
will be interpreted as a codes of ASCII. Return to the decoder 
"ZX-SPECTRUM" occurs command "COPY".


LPRINT CHR $ 0; S - switch
with the interface "CENTRONICS" to "RS
232 "

LPRINT CHR $ 0; P - Return of
"RS 232" K "CENTRONICS"

POKE 23697, n - where "n" specifies the number of characters 
per line printera.Pri initialize printer ustanavlivlen to 80 
characters per line POKE 23728, n - speed

via RS 232. When initializing
1200 baud.

n rate n rate n rate
------------------------------- 1 75 4 300 7 2400
2 110 5 600 8 4800
3 150 6 1200 9600 9



        BASIC COMMANDS

       Printer output

LPRINT - print to the printer

LLIST - print to a printer listing

COPY - screen output to printer
graphical form.



   Initializes the printer enough to make one time after
turn on the computer or after
command "NEW".



  Software compatibility

      Printer driver.


   As you can see, the implementation of interfaces for the 
printer chip and KR580VV55A

ZX-LPRINT schematically different
from each other and, therefore, software support (printer 
driver), will also vary from each other.



   There are many
software tools for working with
printer as a single driver
and with others. They are incompatible.


   Below we will try to show
you how you can combine tools with different
printer drivers.


        Printer Driver

       AT IMS KR580VV55A.


   IC is a programmable KR580VV55A
Interface Adapter (PIA). In
PIA consists of three 8-bit parallel I / O port (see above 
description). 


   Below we provide a standard
program of the printer driver on
IC KR580VV55A. This driver
can occur in many
programs that work with
a printer connected via
KR580VV55A.


 N! Mnemonic! Comment
------------------------------- 10! LD A, # 98! Configuring PIA:
 20! LD C, # 7F! Channel A input
 30! OUT (C), A! Channel B / O

   ! ! C1-channel output

   ! ! Channel C2-entry
 40! LD C, # 5F! Clear signal
 50! OUT (C), C! GATE
 60! LD C, # 3F! Issue bytes
 70! OUT (C), A! In the printer
 80! LD C, # 5F! Poll
 90! M1 IN A, (C)! Signal
100! RLA! BUSY
110! JR C, M1!
120! LD D, # FE! A signal
130! OUT (C), D! GATE
140! M2 DEC D! Delay
150! JR NZ, M2! GATE
160! OUT (C), C! Clear signal
170! RET! GATE. EXIT.



   The driver consists of
two parts:

1. Rows 10 - 50 - Setting
PIA;

2. Rows 60 - 160 - Issue bytes to the printer, which is 
contained in register A.



   As you can see from the above program listing, the addresses 
of external devices with respect to Z80 are as follows: 

# 7F - control register PIA;

# 5F - Port C (C1-output gate,
C2-input BUSY);

# 3F - Port B (the output data byte
on the printer).



   Port A, having an address # 1F,
reserved in many schemes
a Kempston joystick.


        Printer Driver

       ZX-LPRINT (MK III).


   The driver comes in two forms: resident and non-resident. 
Resident driver stored in ROM (see Figure 2) and called it only 
from 48K mode teams LLIST, LPRINT, COPY.

Many programs can also access this drayveru.Kak
work with such a driver, see above. It should be noted that
This driver runs only
Working from BASIC through the stream
# 3. For example, the command: LLIST and
LIST # 3 are identical.



   Non-resident driver is inserted into the body of some 
programs (also as driver ICs KR580VV55A) and upralyaet printer

"Bypassing" ROM resident driver.



   Below we provide a standard
printer driver ZX-LPRINT, which is used in many
programs, both in the 48K mode,
and a 128K-mode (ie it does not
uses the system variables
operating system).



 N! Mnemonic! Comment
------------------------------- 10! M1 IN A, (# 7B)! Poll
 20! AND # 80! Signal
 30! JR Z, M1! BUSY
 40! PUSH BC! Delay
 50! LD B, # 40! GATE
 60! OUT (# FB), A! Issue bytes
 70! M2 OUT (# 7B), A! Issue GATE
 80! DJNZ M2! Delay
 90! OUT (# FB), A! Hide GATE
100! POP BC!
110! RET! Output



   As you can see from the above program listing, the addresses 
of external devices with respect to Z80 are as follows: 

# FB - input / output data without
Strobe

# 7B - data input / output from the gate.


   Many drivers line
40,50,80,100 programs often
No, because there is no need to introduce a delay for
signal GATE. But if your
Printer signal GATE is critical
on time parameters, it is best to introduce 
zaderzhku.Nominalnoe number of delays is selected in line 50. 
You can start with maximum # FF, and reducing the pick up to 
par. (For example, Printer ROBOTRON 6329 Par

is # 40.)


   The above drivers
printer may vary slightly in some programs,
but the basic organization of the software support is as well 
as in the above listings. 

   Now that we have in front of him
standard printer drivers,
You can embed them in one way or
another program, knowing how you
implemented in a computer printer interface, ie achieve
compatibility of programs with your
computer.


   Below, an example program
"ARTSTUDIO", we show how
You can achieve compatibility
printer driver.



      Program Settings

          "ARTSTUDIO".


   The program "ARTSTUDIO" is the most powerful and flexible 
among the currently existing graphical editors for computer 
class "SPECTRUM". 

The program was created in the calculation
to any user - both beginners and artists engaged in creating 
professional graphic designs. 


   The program is istallyatsionnoy (install programm) is with
means it can be installed
(A) a working copy of the program, which will focus
a specific configuration for your external devices (printer,
keyboard, joystick, user interface, driver, etc.).


   To create a working copy
you need to have the original
disk (original disk), which
written Installs program, and
assigned to disk (destination
disk), in which you want to create (install) working
copy.

   The program "ARTSTUDIO" exists in two versions: 48K and
128K. All configuration steps
program, described below,
valid for the two options.


   In order to competently
configure "ARTSTUDIO",
to work with a particular printer in graphics mode, you
know the basic commands to your
printer. These commands are
in the operating instructions for
your printer. If you do not
instructions to the printer, then lower
The basic command codes
EPSON-compatible printers.


   So, we proceed to set up
program.



   After downloading the program "ART
S128 ", you will see a message"
ART STUDIO 128K install
programm ", which says
that the program is
installation.


   Next, the program asks you
where you will install
program - on tape or on
disc. You will need to choose
specific external support.


   After selecting a media program displays the following table
and the question:

1 .... User-defined keys
2 .... Interfase 2 joystisk
3 .... Kempston joystick
4 .... Cursor keys / joystick
5 .... AMX mouse
6 .... Kempston mouse

  Select input device?

   This table and the question requires you to select a specific
input device that allows you to manage the program. You need to 
press specific figures.



   To select a keyboard, we introduce the number 1.


   Next, the program will require
identify certain key
directions and selection commands.


   The program then asks:


   Are you using an 80-column
dot matrix printer (y or n)?

ie Will you use
80-column (narrow), the matrix
printer. If you have a printer with
other characteristics, then you
meet 'n'.

   Next, the program will print the following table, the 
question: 

1. Kempston 'S' Centronics
2. Kempston 'E' Centronics
3. Tasman type A Centronics
4. Tasman type B / 1 Centronics
5. Tasman type B / 2 Centronics
6. Tasman serial RS232
7. Hilderbay Centronics
8. Morex Centronics
9. Morex RS232
10. ZX Interfase 1 RS232
11. ZX Lprint II / III Centronics
12. ZX Lprint II / III RS232
13. Micro Peripherals Centronics
14. Direco Centronics
15. Dk'tronics Centronics
16. AMX Centronics
17. Indescomp Centronics
18. Indescomp RS232
19. Spectrum +2
255. User-own driver


   The table shows that from
You need to select the controller
and the type of interface through which
connected to your computer to your printer. This choice is 
necessary in order program to be established

specific driver in the program.
If the table you will not find
way to connect your printer (eg via IMS
KR580VV55A), you can choose 255 - User-own driver.
After such a selection program
will sozdavt control codes
for the printer, but a driver you
will need to insert themselves into
created a program (as
done will be discussed below).


   For example, we will install the software for the printer ML
6312, which is the EPSON
Compatible.


   Our printer is connected via
ZX-LPRINT interface
CENTRONICS, ie choose
the table number 11.


   Next, it asks:


   Enter number of wires in
print heard (7 or 8)?


   Here we are asked to choose how many needles (7 or 8)
could be used printer
the derivation of the picture.


   To the question: Is the top wire
the mb (y or n)? Need to answer 'y'. Here you set the line 
numbers of needles and number of bits output bytes.




   Next, it asks:


   Enter control codes to be
sent to the printer before a
screen dump, separated by
commas?


   The program asks you to enter
control codes with which your printer should be
prepared for printing, as well as
any other preparatory
codes (carriage return, etc.).


   For our printer, we introduce:


   27,65,8 - in this case, this
chain code corresponds to the command 'set the interval at
8 / 72 of an inch. "


   Numbers are entered in decimal
the form of a comma.


   To the question: Enter number of
dots in single denisty mode? You
must enter the number of points
printed in single density. We will introduce 480.


   Next, it asks:
"Enter control codes ....", on
we must introduce
control codes by which the printer is switched
graphics mode single
density with a given number of
points. We introduce: 27,75,224,1.


   Next, follow the same two
question, but for the double
print density. Answers will
respectively: 960 and 27.76,
192.3.



   To the question: Enter control code
for carriage return? Need
enter the code that corresponds to
carriage return - 13.


   To the question: Enter control code
for line feed? , Enter
code corresponding to the translation
line - 10.


   After answering all questions
the program displays the resulting
table of all the values ​​you entered. If this table
you are satisfied, then the question: Is this correct? Need
answer 'y'. Otherwise, all questions
repeated.



   After the answer
the last question utanovka work program will be completed
on selected external media.
The name of the new program will be assigned to "STUDIO 128".



   SELECT MODE GRAPHICS

    Images on the printer.


   At EPSON-compatible printer
You can display a graphic representation of different scales and
density.


   When you configure the program
"ARTSTUDIO" We asked the two modes of graphic images on
Printer: normal density and
double density, with
set of control codes.



   These modes, we asked
following codes:

- The normal density (480 points) - 27,75,224,1

- Double density (960 points)
- 27,76,192,3



   The table below:
You can see that the graphic
printer mode can be changed
and, hence, output to a printer in various
formats.



 Mode Density Code Contents
-------------------------------------------------- --------! 0! 
Single! ESC K! 60 points per inch! ! ! ! ! 
480tochek/8-dyuymovaya line! ! ! ! ! 816tochek/13 ,6-inch line!

-------------------------------------------------- --------! 1! 
Double with! ESC L! 120 dots per inch! ! ! Low! ! 960 
tochek/8-dyuymovaya line! ! ! Speed! ! 1632tochek/13 ,6-inch 
page! -------------------------------------------------- 
--------! 2! Double with! ESC Y! the same density as in the 
re-! ! ! Low! ! regime 1, but faster. !

! ! Speed! ! !
-------------------------------------------------- --------! 4! 
CRT 1! No! 80tochek/dyuym! ! ! ! ! 640tochek/8-dyuymovaya line!

! ! ! ! 1088tochek/13 ,6-inch page!
! ! ! ! Coincides with the density-screen!
! ! ! ! Tew, 10 (this makes it easier once-!
! ! ! ! load screen)!



 Mode Density Code Contents
-------------------------------------------------- --------! 5! 
One by No! 72 pixels / inch! ! ! Other! ! 576 
tochek/8-dyuymovaya line! ! ! (Grafopos-!! 979 tochek/13 
,6-inch page! ! ! Troitel)! ! Horizontal density!

! ! ! ! identical with the vertical that!
! ! ! ! allows to depict the circle!
! ! ! ! sequence without distortion. !
-------------------------------------------------- --------! 6! 
CRT 11! No! 1990 dpi! ! ! ! ! 720tochek/8-dyuymovaya line!

! ! ! ! 1224 tochki/13 ,6-inch page!
-------------------------------------------------- --------! 7! 
Grafopost-No! 144tochki/dyuym! ! ! Roitel with! ! 1152 
tochki/8-dyuymovaya line! ! ! 4-fold! ! 1958 tochek/13 ,6-inch 
page! ! ! Density! "Well, very small images!

! ! ! ! You can display! !
-------------------------------------------------- --------
   This table shows for
Printer ML 6312. Others EPSON
compatible printers can be
some deviations.

   Selecting a graphics mode for
printer control codes defined by the following:

code ASCII ESC * (m) (n1) (n2)
Decimal 27 42 (m) (n1) (n2)
sixteen. 1B 2A (m) (n1) (n2)

where: m = 0 - 7 - graphics mode (see table above)

n1, n2 = 0 - 255 - the number of points.

Number of points calculated by
the following formula:

N = number of points
n1 = N MOD 256
n2 = INT (N/256)



For example: N = 480 points

n1 = 480 MOD 256 = 224 decimal.
or E0 hex.

n2 = INT (486/256) = 1 decimal.
or 01 hex.


   You can be sure that the same codes we introduced in
setup program "ARTSTUDIO"


   When you configure the program
"ARSTUDIO" you can ask any of the 7 graphics.
For example, on a matter in which
need to specify the behavior of single
print density, the printer, you
enter the following parameters: 640
and 27.2 A, 04,128,2 you ask 4
graphics mode and get
pictures on a printer without any distortion.

Program Settings "ARTSTUDIO"

  Under any printer driver.


   In this section, for example,
program "ARTSTUDIO", we
describe how to configure one or
another program under a certain
printer driver.


   Ie Our goal is to
to find where in the program is a printer driver
and if it does not suit us, then
competently replace it with another.


   Location driver
printer in the body of the program can be
determined using various
disc or cassette program monitors. We use
program "DOCTOR V4".



   With this program, "DOCTOR"
We find a printer driver
file "studio_m". It has the form:


    00 00 00 00 08

    00 00 00 00 1B

    41 08 E0 January 2000

    00 00 1B 4B E0

    01 C0 00 March 2000

    00 1B 4C C0 03

    0D 0A 64 87 6E

    87 6E 87 73 87

    16 00 DB 7B E6

    80 C9 D3 FB D3

    7B D3 FB C9 00


   At first glance, nothing
understandable. But if you carefully
consider this dump, you
understand what is presented here
table settings that we
asked when setting up
"ARTSTUDIO" and followed it -
software printer driver.
We analyze this dump in order:

08 - given the number of needles
Printer

1B 41 08 - command 'set
interval '

E0 01 - number of points under
single density = 480

1B 4B E0 01 - Team inc. graph.
single-mode density

C0 03 - number of points under
double density = 960

1B 4C C0 03 - Team inc. graph.
mode of double-density

0D - code carriage return

0A - linefeed code.


   This first part of the dump contains options to enable 
various modes of the printer. 


   The second part of the dump contain
address challenges of the driver prints
pa and the program itself 'driver
Printer. Consider these codes:

64 87 - Starting Address

6E 87 - Address Call

6E 87 - Address Call

73 87 - Address Call

16 00 - Number of bytes used in the second part of the dump.



   Call is located at the addresses
the program itself is "a printer driver
ZX-LPRINT ":

DB 7B E6 80 C9 - poll signal
BUSY

D3 FB D3 7B D3 FB C9 - Conclusion
bytes to the printer


   Now, knowing the value of the above codes, you can not
resorting to installs-program
set up a working copy of the program "ARTSTUDIO" at will. Ie 
You can insert themselves into the program different settings 
for the printer: number of needles, number of dots, a graphic 
image. And so are you can insert into your program

printer driver.



   For example, a printer driver for IMS KR580VV55A second
part of the dump will be as follows:


    64 87 6E 87 92 87

    94 87 4F 00 98 3E

    0E 7F ED 79 0E 5F

    ED 49 3E 1B CD 94

    87 3E 40 CD 94 87

    3E 1B CD 94 87 3E

    55 CD 94 87 3E 00

    CD 94 87 C9 AF C9

    0E 3F ED 79 0E 5F

    ED 78 17 38 FB 16

    FE ED 51 15 20 FD

    ED 49 C9 00


   The program "ARTSTUDIO" configured to work with the printer 
driver for IMS KR580VV55A. 



   Now you have the skills
to configure any program
under a specific printer driver.


   WARNING! In order to avoid
spoil the program-originals
All changes to the programs it is desirable to produce 
duplicate diskettes! 



       RECEPTION PICTURES

      From any program.


   In this section, we describe
as a "pull" your favorite
picture from any program.


   The easiest way - is
use the "magic button" - MAGIC.



   Pictures "pulled out" as follows: you load
the desired game. After
appears on the screen the desired image, you press the "magic
button and the entire program from the computer memory along 
with a screen area can be rewritten to a floppy disk that you 
previously insert into the drive.



   The recorded files to a floppy disk
automatically assigned a name
"@". Now, in order to
"Pull" only a picture of
This magic-file, use the following short
program.

10 INPUT "NAME"; N $
20 RANDOMIZE USR 15619: REM: LOAD
"@" CODE 16384,6912
30 RANDOMIZE USR 15619: REM: SAVE
N $ CODE 16384,6912

   The pictures you can handle any graphics editor: ARTSTUDIO, 
ARTIST and etc.



    Command codes for Printers


   Special command codes transmitted to the printer series 
ESCAPE sequences.



   ESCAPE - sequence
consists of a package (27) and the subsequent alphanumeric
signs or symbols. The table below is a list of control 
programs. In parentheses is indicated decimal code functions. 
In the angular brackets indicate the characters that can be 
typed on the keyboard. Symbols N, N1, N2 - this number in the 
range from 0 to 256.


 -------------------------------------------------- ----! 
FUNCTION! CONTENT!  
-------------------------------------------------- ----! BEL 
(7)! Audible alarm! ! BS (8)! Return to step!

! HT (9)! Horizontal tab!
! LF (10)! Newline!
! FF (12)! Translation format!
! CR (13)! Carriage return!
! SO (14)! The inclusion of the Russian font!
! SI (15)! The inclusion of Latin letters!
! DC1 (17)! The choice of printer!
! DC3 (19)! Cancel printer!
! CAN (24)! Cancel a string!
! DEL (127)! Removing the sign!
! ESC <*> N, N1, N2! Mode Selection graphic!
! ESC <-> 1! Enabling the underscore!
! ESC <-> 0! Disable underline!
! ESC <0>! The choice of 1/8-inch intervals!
! ESC <1>! Choosing 7/96-dyuymovogo interval!
! ESC <2>! The choice of 1/6-inch intervals!
! ESC <3> N! Choosing n/288-dyuymovogo interval!
! ESC <8>! Lock the sensor end of the paper!
! ESC <9>! Inclusion of the sensor end of the paper!
 -------------------------------------------------- ----! 
FUNCTION! CONTENT!  
-------------------------------------------------- ----! ESC 
<@>! Initiating the printer! ! ESC  N! Choosing 
n/96-dyuymovogo interval! ! ESC  N! Selecting page length to 
n lines! ! ESC  0N! Selecting page length to n inches!

! ESC ! Setting horizontal tab!
! ESC <E>! Selecting an underlined the regime!
! ESC <F>! Cancel underlined the regime!
! ESC <G>! Selecting the mode double whammy!
! ESC <H>! Canceling the double whammy!
! ESC <J> N! Submission of papers on n/288 inches forward!
! ESC <j> N! Back Feeding on n/288 inches!
! ESC <K> N1, N2! Mode single, graphic-!
! ! density!
! ESC <L> N1, N2! Mode graphic double!
! ! density!
! ESC <M>! Step selection "ELITE", compacted mode!
! ESC <N> N! Choosing pass through the perforations!
! ESC <O>! Cancel passes through the perforations!
! ESC <R>! Choice of characters!
! ESC  0! Select to print a superscript!
! ESC SI! Inclusion of compressed mode!
 -------------------------------------------------- ----! 
FUNCTION! CONTENT!  
-------------------------------------------------- ----! ESC 
 1! Select to print the lowercase! ! ESC <T>! Cancel print 
top. and the subscript! ! ESC <W> 1! Selecting Advanced mode!

! ESC <W> 0! Cancel extended mode!
! ESC <Y> N1, N2! Selecting a graphics mode dual density!
! ! surface at high speed!
 -------------------------------------------------- ----


   This table command codes
refer to the printer ML 6312.
Others EPSON - compatible
printers may be some
deviations or additions, but
they are insignificant.



          LITERATURE.

1. USERS GUIDE
"SPECTRUM" - FIRM "VA PRINT".

2. A. Larchenko, N. Rodionov
"ZX-SPECTRUM FOR USERS AND
Programmer ".

3. A. Larchenko, N. Rodionov "dialect BASIC.



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