DRAPER PASCAL Version 2.1 ; Copyright (C) 1989 by Norm Draper ; For the Atari 400, 800, XL, or XE series computers



  • Draper_Pascal_Manual.pdf(info) ; Draper Pascal 2.1 manual from Norm Draper ; registered users version with complete description of all definitions ; AtariWiki says mega thank you to Norm Draper for giving this manual into PD. We really appreciate your help and contribution to the Atari community. Be sure, you are in our hearts. Thanks you so much. We further thank Kay Savetz so much much for getting in contact with Norm Draper and sending us this lost to believe manual after 29(!) years... That is so amazing! Thank you Kay, we all appreciate your work so much. :-)
  • Draper Pascal 2.1.pdf(info) ; Draper Pascal 2.1 disk based documentation

Disk Based Documentation#

This document contains the "Getting Started" section plus other sections from the actual Draper Pascal manual. It is designed to get you up and running and doing useful things with Draper Pascal in a very short time. It does not, however, contain a detailed description of all the Draper Pascal definitions or pretend to be a comprehensive tutorial or user's reference. Registered users will receive the actual Draper Pascal manual which does contain a complete description of all definitions plus other information. Details on registering are in the last section titled "Registration Form".

The Shareware Concept#

Draper Pascal is distributed on a Shareware basis. You may use Draper Pascal without charge for the purpose of evaluating it's suitability for your use. If you find that Draper Pascal is worth continuing to use, then you are requested to become a registered user and gain the additional benefits that go along with it. Simply complete the registration form and mail it in to us with the very reasonable payment of only $15.00. When you register your copy of Draper Pascal, you'll receive the latest version of the software if your registered version is not current, along with a comprehensive printed user manual.

If you have received this copy from a Users' Group, "Software Library" or "SIG", and have paid a small fee (usually $3 to $10), you have NOT acquired the registered rights or continued right to use Draper Pascal. This fee was for the convenience of obtaining the diskette with Draper Pascal on it. The fee does NOT apply to the registration fee.

You may freely copy Draper Pascal for distribution under the Shareware concept, without charge.

You may NOT charge any fee for the Draper Pascal program or documentation without our written approval.

You may NOT distribute Draper Pascal or it's documentation in connection with ANY commercial venture, product, publication or service unless you obtain the royalty-free license by registering.


  • Draper Pascal is a complete package allowing the user to create, compile, and execute programs written in the Pascal language.
  • Many features from both UCSD and ISO standard Pascals plus many extensions, such as sound and graphics, to make use of the versatile Atari hardware.
  • Pascal structured programming features, including IF-THEN-ELSE, WHILE-DO, CASE-OF-ELSE, FOR-TO/DOWNTO-DO, and REPEAT-UNTIL are included.
  • FUNCTIONs and PROCEDUREs using local or global variables. Integer type variables can be passed directly.
  • Data types supported include: Character, String, Integer, Real, Boolean, Record, and File. One and two dimension arrays are also supported for all data types other than File and Record.
  • Only one disk drive and 48K RAM are required. Multiple, and double density, disk drives are supported.
  • Machine language subroutines may be loaded and called.
  • Program chaining is supported.
  • No limit on source program size. "Include" files are supported.
  • One-pass compiler generates pseudo code directly.
  • Maximum program pseudo code size is about 30K bytes.
  • Textual compiler error messages.
  • Execution debugging features include instruction trace and stack display.
  • Special options for error display and break key disable.
  • Single keystroke program execution repeat, exit to DOS, or exit to Main Menu program are featured.
  • Includes Editor program to create, modify, and print Pascal source files, or other text type files.
  • Includes Main Menu program (Pascal source included) for easy select of Compiler, Editor, or utility functions, such as directory or file listing. Main Menu program may be replaced with a user written program to create a turnkey operation.
  • Ramdisk support. Details provided to registered users.
  • Works with most popular versions of DOS.
  • Easy to use. No linking required. Compile and execute immediately.
  • Royalty free license available to registered users.
  • Includes sample programs.
  • Comprehensive user manual provided to registered users. Complete examples and BASIC equivalents given for each reserved word.


Draper Software welcomes you to the world of Pascal for the Atari 400/800, XL, and XE series Computer systems.

What is Pascal?#

Pascal is a high-level structured programming language developed by Niklaus Wirth in 1971. It is easy to understand and well suited for program development and maintenance.

What is Draper Pascal?#

Draper Pascal is not a "standard" Pascal. It has a number of commands which are exactly like ISO and UCSD versions, some which are similar, and many "extensions" which bring out the true power of the Atari computer in an easy to use manner. It was designed to require only one disk drive for operation, but not be limited to only one. At this time, it has been shown to work with all hardware and software configurations where enough memory is provided. This implementation also has a number of commands which are familiar to Atari BASIC users, such as POKE, PEEK, SETCOLOR, NOTE, POINT, etc..

About this manual#

This manual is intended to familiarize you with all the features of Draper Pascal. It is not intended to teach you how to program in Pascal. However, if you already know Atari BASIC, then you can understand the Pascal statements more easily by referring to their BASIC equivalents shown after the definition of each Pascal reserved word in the complete manual provided to registered users. It is recommended that you read this manual completely to be familiarized with its features and restrictions.

What is Draper Pascal made of?#

This implementation of Pascal is made up of three main components. They are the Supervisor (sometimes referred to as runtime routines), the Compiler, and the Editor. The Supervisor is a high performance machine language program which simulates a 16-bit pseudo computer. The Compiler translates Pascal source code into pseudo-code instructions to be executed by the Supervisor. The Editor is used to enter and modify Pascal source programs. It may also be used to edit data files, or BASIC programs which have been LISTed to a disk or tape. These components are explained in detail within this manual.

For a description of the various files included on the supplied diskette, refer to the 'System Information' section.

About the DOS#

Draper Pascal can be used with most popular Disk Operating Systems. It has been tested with Atari DOS 2.5, SpartaDOS 3.2d, and MYDOS. You should format a diskette with DOS on it to contain the Draper Pascal system. Since the Draper Pascal Supervisor is named AUTORUN.SYS, it will execute immediately after the disk is booted. For XL and XE computers, you do not need to hold down the Option key while booting unless you are using SpartaDOS. If using SpartaDOS, you may want to rename AUTORUN.SYS to PASCAL.COM and create a STARTUP.BAT file containing the following two lines:

This documentation file is not required to be on that same diskette.

Ramdisk support#

Draper Pascal supports the use of the "Ramdisk" capability provided by using a DOS that supports a ramdisk like Atari DOS 2.5 or SpartaDOS 3.x with an Atari computer system having sufficient memory to support the ramdisk. While using this feature, the Editor takes less than two seconds to load and the Compiler takes less than three seconds. Details on setup and use of this feature are provided in the complete manual provided to registered users.

Getting Started#

This section is intended to show by example how to use the Draper Pascal system. You will edit, compile, and run a sample program. Information displayed by the computer is shown in normal type while responses to be entered by you are shown underlined with dashes (---). To begin with, make sure you have 48K RAM installed and no cartridge in place. Boot the disk now by placing it in disk drive 1 and turning on the power to the Atari computer. After the Supervisor has finished loading, you will see a screen that looks like this:


1 - Run Program

2 - Disk Directory

3 - Compile Program

4 - Edit a Program

5 - Exit to DOS

6 - List a file

7 - Trace on
                 DRAPER SOFTWARE

               A - Add line(s) at end
               C - Change line(s)
               D - Delete line(s)
               E - Edit a line
               F - Filer menu
               I - Insert before line
               L - List line(s)
               M - Menu
               P - Print line(s)
               Q - Quit
               S - Scan line(s)
               X - Exit to Compiler
       A,C,D,E,F,I,L,M,P,Q,S,X,?->F           Select Filer menu

               A - Append file
               D - Directory list
               L - Load file
               S - Save file

               L                              Load a file
       Enter filename  -> SAMPLE1             Enter the name of the file
                          -------             to be loaded. The name of
                                              the last file edited,
                                              compiled, or run will be
                                              filled in by the Editor.
                                              You may have to overtype
                                              it with the name shown.
       A,C,D,E,F,I,L,M,P,Q,S,X,?->L           List the file on the
                                  -           screen

       Line from ->                           Just press RETURN for
                   -                          'Line from' and 'Line to'.
       Line to   ->                           This will give a list of
                   -                          the entire program in

         2:VAR I,J,K,W,X:INTEGER;
         4: MAXGRAPH(19);
         5: GRAPHICS(19);
         6: X:=0;
         7: REPEAT
         8: FOR W:=3 TO 50 DO
         9:  BEGIN
        10:    FOR I:=1 TO 10 DO
        11:    BEGIN
        12:     FOR J:=0 TO 10 DO
        13:      BEGIN
        14:       K:=I+J;
        15:       COLOR(J*3/(I+3)+I*W/12);
        16:       PLOT(I+8,K);
        17:       PLOT(K+8,I);
        18:       PLOT(32-I,24-K);
        19:       PLOT(32-K,24-I);
        20:       PLOT(K+8,24-I);
        21:       PLOT(32-I,K);
        22:       PLOT(I+8,24-K);
        23:       PLOT(32-K,I)
        24:      END
        25:    END
        26:  END
        27: UNTIL X=99 (* UNENDING LOOP *)
       A,C,D,E,F,I,L,M,P,Q,S,X,?->I           Let's insert a comment
                                  -           before line 15.
       Line -> 15

        15:       (* MY FIRST EDIT *)         Enter the data to be
                  -------------------         inserted when prompted for
        16:                                   line 15. Just press RETURN
            -                                 when prompted for line 16.
                                              This will terminate insert

       A,C,D,E,F,I,L,M,P,Q,S,X,?->L           List again to verify that
                                  -           the change was made

       Line from ->
       Line to   ->

         2:VAR I,J,K,W,X:INTEGER;
         4: MAXGRAPH(19);
         5: GRAPHICS(19);
         6: X:=0;
         7: REPEAT
         8: FOR W:=3 TO 50 DO
         9:  BEGIN
        10:    FOR I:=1 TO 10 DO
        11:    BEGIN
        12:     FOR J:=0 TO 10 DO
        13:      BEGIN
        14:       K:=I+J;
        15:       (* MY FIRST EDIT *)
        16:       COLOR(J*3/(I+3)+I*W/12);
        17:       PLOT(I+8,K);
        18:       PLOT(K+8,I);
        19:       PLOT(32-I,24-K);
        20:       PLOT(32-K,24-I);
        21:       PLOT(K+8,24-I);
        22:       PLOT(32-I,K);
        23:       PLOT(I+8,24-K);
        24:       PLOT(32-K,I)
        25:      END
        26:    END
        27:  END
        28: UNTIL X=99 (* UNENDING LOOP *)
       A,C,D,E,F,I,L,M,P,Q,S,X,?->F           Let's save the program
                                  -           back to disk drive 1
                                              under the same name.

               A - Append file
               D - Directory list
               L - Load file
               S - Save file

       Enter filename  -> SAMPLE1
       A,C,D,E,F,I,L,M,P,Q,S,X,?->X           Now let's exit directly to
                                  -           the Compiler.

                Draper Software

                Pascal Compiler

                  Version 2.1

                Copyright 1989
                by Norm Draper

                Enter Filename:
                SAMPLE1                       Enter name of program to
                -------                       be compiled. The name of
                                              the last program edited,
                                              compiled, or run will be
                                              filled in by the

       Enter List Output Filespec
       Default is E:                          Just press RETURN at this
                    -                         point to have the compile
                                              list directed to the

       0000 VAR I,J,K,W,X:INTEGER;
       0003 BEGIN
       0003  MAXGRAPH(19);
       0017  GRAPHICS(19);
       001B  X:=0;
       001E  REPEAT
       0022  FOR W:=3 TO 50 DO
       002A   BEGIN
       0035     FOR I:=1 TO 10 DO
       003D     BEGIN
       0048      FOR J:=0 TO 10 DO
       004F       BEGIN
       005A        K:=I+J;
       0062        COLOR(J*3/(I+3)+I*W/12);
       008A        PLOT(I+8,K);
       0098        PLOT(K+8,I);
       00A6        PLOT(32-I,24-K);
       00B8        PLOT(32-K,24-I);
       00CA        PLOT(K+8,24-I);
       00DC        PLOT(32-I,K);
       00EA        PLOT(I+8,24-K);
       00FC        PLOT(32-K,I)
       010A       END
       010A     END
       010C   END
       011C  UNTIL X=99 (* UNENDING LOOP *)
       0142 END.
       ADDR   NAME
       ---- --------
       0003 I
       0004 J
       0005 K
       0006 W
       0007 X
       5 Compiler table entries used
       *** Program Execution Completed ***    Press the SELECT key at
       Highest Stack Address Used = $AFF8     this point to take us to
       <START>Repeat,<SELECT>Menu,<ESC>Exit   the main menu.

                  DRAPER PASCAL

                   VERSION 2.1

               1 - Run Program

               2 - Disk Directory

               3 - Compile Program

               4 - Edit a Program

               5 - Exit to DOS

               6 - List a file

               7 - Trace on

                  Copyright 1989
                  by Norm Draper

              1                               Select '1' to run the
              -                               program that was just

         Enter name of program to be run

              SAMPLE1                         The name of the last
              -------                         program edited, compiled,
                                              or run will be filled in
                                              by the main menu program.
                                              Overtype the name if you
                                              want to run a different

At this point you should have a nice kaleidoscope pattern being displayed on your television screen. To stop it, press the BREAK key. To repeat execution, press the START key. To return to the main menu, press the SELECT key. To exit to DOS, press the ESC key.

Another program, SAMPLE2, is also provided for you to practice with. It will display Roman numerals for powers of two between 1 and 4096. Compile it, turn on the trace via the main menu, and run it. After it is finished, press CTRL-T to display the trace table, and CTRL-S to display the stack contents. When prompted for 'Where? Filespec', enter 'E:'. For a description of the stack display line, refer to the 'DUMPSTK' command in the 'Pascal Definitions' section of the manual provided to registered users.

Main Menu#

The Main Menu is the initial program to be run by the Supervisor. It is written in Pascal. The source code is provided for it and you may customize it as you see fit. The disk filename for the source is 'INIT.PAS'. The pseudo code program that is initially executed is 'INIT.PCD'. It would be wise to copy 'INIT.PCD' to another name to be used in case your compile of the menu program is not successful. Or, you could rename INIT.PAS to something else, like NEWINIT.PAS, and compile it to produce NEWINIT.PCD. Then you can use the 'run' option (mentioned below) to test your modified program.

The Main Menu appears as follows:

                  DRAPER PASCAL

                   VERSION 2.1

               1 - Run Program

               2 - Disk Directory

               3 - Compile Program

               4 - Edit a Program

               5 - Exit to DOS

               6 - List a file

               7 - Trace on

                  Copyright 1989
                  by Norm Draper

Each of the menu options will now be explained:

Run Program#

Use this option to execute a program that has previously been successfully compiled. You will see the following prompt:

       Enter name of program to be run
The Main Menu program will fill in the name of the last program edited, compiled, or run. If this is the one you want, all you have to do is press RETURN. If it is not the one you want, just overtype the name shown with the one you want.

Disk Directory#

This option will provide you with a list of all, or selected, files on one of your disk drives. You will receive the prompt 'Filespec?'. If you just press RETURN at this point, you will see a list of all files on the default drive. If you enter 'D2:', you will see all files on drive 2. To show only selected files, use wildcards in the normal manner. For example, enter 'D1:INIT.*' to show only files named INIT with any suffix from drive one. At the end of the list, you will be prompted to press any key to continue. After pressing any key, the Main Menu will be re-displayed.

Compile Program#

This option sends you directly to the Pascal compiler. You will be prompted for the name of the program to be compiled, after the Compiler is loaded. If you have already edited, compiled, or run a program, the name will be shown and may be used by just pressing the RETURN key. For more information, refer to the section of this manual on 'The Compiler'.

Edit a Program#

Control is transfered to the Draper Pascal Editor when this option is chosen. For more information, refer to the section of this manual on 'The Editor'.

Exit to DOS#

Pascal execution is terminated by this option. Control is passed to the Disk Operating System.

List a file#

This convenience entry is provided to allow you to view, on the screen, any text file on disk or tape. You are prompted to enter the name of the file to be listed. The file is assumed to reside on the default drive if a colon (:) is not found within the name you specify. At the end of the list, you will be prompted to press any key to continue. After pressing a key, the Main Menu will appear again.

Trace on#

The wraparound internal trace may be turned on (or off) with this option. The trace is used only for debugging purposes and may be viewed at program termination time by pressing CTRL-T. Program execution speed is slightly degraded while the trace is active. You will be prompted to enter the number of trace entries to be maintained by the system. Each trace entry requires 10 bytes of storage at the high end of memory. The trace may not be used during graphics displays because screen memory is also at the high end of memory. To turn the trace off and remove the memory allocation of the trace table, enter zero when prompted for the number of entries to maintain. The trace format is described in the manual provided to registered users.

The Editor#

The Editor is used to create, modify, and save Pascal source files. It may also be used to process other text type files, like BASIC programs which have been LISTed to disk or tape. It is a line oriented editor. Combined with some type of formatting program, it may be used for word processing applications. The entire source to be edited must be in memory at one time. If your Pascal program will not fit within the limits of the Editor, then you can use the INCLUDE feature of the Compiler to allow segments of a program to be edited separately. Refer to the section on "THE COMPILER" for more information on the INCLUDE feature. Source code for the Editor is listed in the manual provided to registered users. Some key points to be noted about this editor are as follows:

  1. Each line is referred to by line number, however, no line numbers are stored either internally or on the disk or tape.
  2. Each line may contain up to 80 characters. This may be changed by altering the constant called MAXLENGTH and re-compiling the Editor. A source listing of the Editor is provided to registered users.
  3. A maximum of 250 lines of text may be edited at one time. This may be changed by altering the constant called MAXLINES and re-compiling the Editor. An increase in MAXLINES should correspond with a decrease in MAXLENGTH, and vice versa. A source listing of the Editor is provided to registered users.
  4. When entering or editing a line, the line must be terminated by pressing the RETURN key.
  5. As lines are inserted into, or deleted from, the source file, the remaining lines are automatically renumbered.
  6. A line of source may extend onto more than one screen line.
  7. Due to operation of the Atari operating system, a blank line may not be directly entered. To enter a blank line, you must first enter a non-blank character (like a period), then use the Editor Change command to change the character to a space.
  8. Input operations (Append and Insert) are terminated by entering a null line (just pressing the RETURN key).
  9. The BREAK key is disabled by the Editor to prevent loss of data. It is enabled again at termination of the Editor.
  10. If you enter or change data then try to Quit or exit to the Compiler without first saving the data onto disk, you will receive an option to either save the data or ignore it and continue.
  11. Cassette tape files may be loaded, edited, and saved by the Editor. The Compiler does not support tape input, though. You would first have to load the file from tape, with the Editor, then save it to disk.

Wiki-Editing pending

                                EDITOR COMMANDS

                                General Prompts

       The following prompts are general in nature and are common among
       many of the editor commands to be described below.

       Line ->

       You are prompted to enter one line number, as opposed to a range
       of line numbers. It is used by the INSERT Editor command and
       refers to the line before which the inserted line(s) will be

       Line from ->

       This is the first prompt for a range of line numbers. Enter the
       low number of the range. If you just press RETURN, line number 1
       is assumed.

       Line to   ->

       Enter the high line number in the range desired. If only one line
       is to be acted upon, that number must be entered in both this
       prompt and the one mentioned above. If you just press RETURN, the
       highest line number in the buffer will be assumed. If the number
       you enter is less than the 'Line from' value, the 'Line from'
       value will be used here.


       Draper Pascal 2.1                                     The Editor

       Enter filename  ->

       This prompt is shown when loading, appending, and saving files.
       The last filename used is filled in after the arrow. If this is
       the file you wish to use now, then all you have to do is press
       RETURN. A full filespec may be entered, but is not required. If a
       colon (:) is not found within the filename specified, then the
       default drive is assumed. If the filename given does not contain a
       period (.), then a suffix of .PAS is assumed.

                                  The Commands

       A - Add line(s) at end

       This command is used to add lines after the last line currently in
       the buffer. If the buffer is currently empty, then line 1 will be
       assumed as the starting point. In this manner, you can create a
       new file if one has not been loaded. You can append as many lines
       as you like. When you are finished entering lines, just press
       RETURN without entering any data on the line (null line).
       Prompts used: None

       C - Change line(s)

       The Change command allows you to change one specified string
       pattern to another for the first occurance in each line within the
       range of lines specified. After being prompted for the line number
       range, you are asked for the data to 'Change from ->' and 'Change
       to   ->'. Enter any string of characters at each prompt. Imbedded
       blanks are allowed. If you just press RETURN for the 'Change to'
       prompt, the first occurance of the 'Change from' data within each
       line will be deleted.
       Prompts used: 'Line from', 'Line to', 'Change from', 'Change to'

       D - Delete line(s)

       This command allows you to delete a line or a range of lines from
       the file in memory. The whole file in memory will be deleted if
       you just press RETURN when prompted for both 'Line from' and 'Line
       to'. Be aware that all lines following the range deleted will be
       renumbered, to fill the gap just made. If you desire to delete a
       number of line ranges, delete those with the highest numbers first
       and proceed toward the beginning of the file. That way, you won't
       have to do a LIST after each range delete to find out what the new
       line numbers for the following lines are.
       Prompts used: 'Line from', 'Line to'


       Draper Pascal 2.1                                     The Editor

       E - Edit line(s)

       The Edit command is used to edit (or make individual changes to) a
       line or range of lines that already exist in memory. If a range is
       specified, the lines are presented to you one at a time. As each
       line is presented, you may use any of the normal Atari editing
       keys (like right and left cursor, insert, delete), to alter the
       data. Just press RETURN when you are finished with each change. If
       you don't want to make a change to a line shown, just press
       Prompts used: 'Line from', 'Line to'

       F - Filer menu

       The Filer is a subsystem which handles communication with an
       external device (disk or tape). The features provided are as

           A - Append file

           A file is read from disk or tape and added to the end of the
           file currently in memory. The data in memory prior to the
           append remains unchanged.
           Prompts used: 'Enter filename'

           D - Directory list

           This command is used to provide a directory list of the
           different files on a diskette. You are prompted for
           'Filespec?'. Enter the disk drive number and selection
           criteria for the directory list. If you just press RETURN you
           will see a directory list of all files on the default drive.
           To see all files on drive two, enter 'D2:' or 'D2:*.*'. To see
           only files with a suffix of PAS on drive one, enter
           Prompts used: 'Filespec?'

           L - Load file

           This is the way to load a file into memory from disk or tape.
           If any data was currently in memory, it is deleted and
           replaced by the file read in.
           Prompts used: 'Enter filename'


       Draper Pascal 2.1                                     The Editor

           S - Save file

           Data is copied from memory to disk or tape with this command.
           The data currently in memory remains unchanged. You are
           prompted for filename and may use whatever name you wish. It
           is not necessary to save a file under the same name as was
           used to load the file. You should save data to disk frequently
           if you are making extensive changes. That way you won't have
           to re-do as much if something goes wrong.
           Prompts used: 'Enter filename'

       I - Insert before line

       This command allows you to insert one or more lines at any point
       within the file in memory. The inserted data is placed before the
       line number you specify. To terminate insert mode, just press
       RETURN without entering any data on the same line (null line).
       Note that all lines after the point of insertion will
       automatically be renumbered.
       Prompts used: 'Line ->'

       L - List line(s)

       One or more lines of data from memory are listed on the screen
       with this command. During the list, you may stop the scrolling by
       pressing either the space bar or RETURN. To resume scrolling,
       press any other key other than ESC. The ESC key may be pressed to
       prematurely terminate the listing.
       Prompts used: 'Line from', 'Line to'

       M - Menu

       The main Editor menu is presented in response to this command. A
       question mark (?) may also be used to display the main menu.
       Prompts used: None

       P - Print line(s)

       This command is used to create a list of data in memory on a
       printer attached to the Atari parallel port (P:). Internal line
       numbers are also directed to the printer although they do not
       actually exist within the file on disk or tape.
       Prompts used: 'Line from', 'Line to'


       Draper Pascal 2.1                                     The Editor

       Q - Quit

       This command is used to exit from the Editor when you are finished
       editing your data.  Control is given to the Main Menu program. If
       you have changed the data in memory and have not saved it prior to
       quitting, you will be given the option of saving the data or
       ignoring the changes and exiting. If you are going to compile a
       Pascal program immediately after quitting the Editor, you may use
       the 'X' command described below.
       Prompts used: None

       S - Scan line(s)'

       This command allows you to display all lines within a specified
       range which contain a specified character string. The character
       string may contain any characters, including imbedded blanks. To
       temporarily stop the listing, press either the space bar or
       RETURN. To abort the listing, press ESC. Press any other key to
       continue as normal.
       Prompts used: 'Line from', 'Line to', 'Scan for'

       X - Exit to Compiler

       This command terminates the Editor and transfers control directly
       to the Compiler. If the file in memory has been changed but not
       saved prior to the Exit command, you will be prompted to either
       save the file or ignore the changes and proceed to the Compiler.
       Prompts used: None


       Draper Pascal 2.1                                   The Compiler

                                  The Compiler

       The Compiler is used to translate words that we humans understand
       into "words" that the computer can understand. The computer words
       are referred to as pseudo-code, or p-code for short. These
       pseudo-code instructions are understood and executed by the

       This is a single pass goal oriented compiler. It expects the
       proper syntax for a statement. If correct syntax is not found, the
       compilation stops, and an error number with associated text
       description is displayed. At this point, you are given the option
       of quitting or returning to the Editor to correct the problem and
       do the compile again.

       The Compiler itself is written in Draper Pascal and occupies about
       28K of RAM memory space.

       The first prompt from the Compiler is 'Enter filename:'. The name
       of the last program edited, run, or compiled is filled in for your
       convenience. If this is the one you want, just press RETURN. If it
       is not the one you want, just overtype it with the name you
       desire. The name you provide will become the new default name for
       the Editor, Compiler, and Main Menu 'Run' option. No suffix is
       allowed when specifying filename. The Compiler will add the
       standard '.PAS' to it for you. If the source does not reside on
       the default disk drive, then you must prefix the filename with
       'Dn:' where 'n' is the disk drive number where the source resides.
       The default disk drive is normally disk drive number one, but is
       changed to the Ramdisk drive number if you are taking advantage of
       the Ramdisk feature of a Disk Operating System that supports it.
       Ramdisk initialization is explained in the manual provided to
       registered users.

       The next prompt is 'Enter List Output Filespec'. The default (if
       you just press RETURN) is the screen (E:). The list output may go
       to any normal output device, such as printer (P:) or disk

       A number of additional points are mentioned below:

        1. Comments are delimited by '(*' on the left end and '*)' on the
           right end. Any characters may appear within comments. Comments
           may appear anywhere within the program.

        2. 'Include' files are supported. You may have procedures,
           functions, or any part of a program included in a compile,
           even though it is not actually part of the file being
           compiled. It is a variation of a comment which allows you to
           do this. The format is as follows:

           (*$I XXXXXXXX *) or (*$I D1:XXXXXXXX *)


       Draper Pascal 2.1                                   The Compiler

           The dollar sign and 'I' must be right next to '(*' and must be
           followed by one space. Then you may mention the 'D' for disk
           and drive number (if other than the default drive is to be
           used). Follow it with a colon (:) and the filename. A suffix
           of '.PAS' will be automatically added to the file name. Then
           have at least one space and '*)'.

        3. Pascal source files must reside on disk.

        4. The output pseudo-code from the compile will be directed to
           the same disk drive that the Pascal source resides on. It will
           be created with a filename suffix of '.PCD'. If you have
           multiple disk drives and the source and pcode will not both
           fit on one disk, have a small file on the output disk with an
           'include' for the source which resides on the other disk.

        5. The hexadecimal offset of the pseudo instructions generated is
           given at the left side of the output listing. This offset may
           be useful for debugging purposes. It may be referred to when
           looking at a program trace (see TRACEON in the Pascal
           Definitions section of the manual provided to registered
           users). It also may be referred to in case of an error message
           or termination caused by pressing the BREAK key. The offset
           shown may not always be accurate. If not exact, the values are
           very close.

        6. The name and stack offset of each variable defined is shown at
           the end of the compile listing. The offset value is shown in
           hexadecimal. Each stack entry is two bytes wide. The first
           three stack entries are reserved for system use. Therefore,
           the offset of the first variable will be 0003, which is
           actually six bytes into the stack. If a variable is defined
           within a procedure or function, the offset shown is relative
           the beginning of that procedure or function.

        7. The program is ready to run immediately after the compile is
           finished. No linking is required. (Some Pascal systems require
           linking of output code after the compile and before

       8.  Nested procedures are supported. You may define one procedure
           within another.

       9.  Recursive procedures are supported. A procedure may call
           itself. If variables are defined within the procedure, they
           are cleared with each entry into the procedure and refreshed
           upon exit from the recursive procedure call.

       10. No forward references are allowed. A procedure may not be
           referenced before it is defined. In most cases, nesting the
           procedures will take care of this problem.


       Draper Pascal 2.1                                   The Compiler

       11. Double density disk drives are supported for both source and
           pcode files. The pcode will be written to the same drive that
           the initial source is taken from.

       12. Only integer type parameters may be passed to procedures and
           functions. Other types of data may be passed by using global
           type variables setup at the beginning of the program (not
           within a procedure or function).

       13. A function may only return an integer type value. Procedures
           do not return values.

       14. Hexadecimal constants and literals are prefixed by dollar
           signs ($).

       15. To write out an integer in hexadecimal format, precede the
           variable name with a percent sign (%).

       16. A total of 170 compiler table entries may be used. One table
           entry is used for each variable definition, procedure name,
           function name, and parameter name used with procedures and
           functions. Table entries for variables defined within
           procedures are re-used following the 'END' for that procedure.
           The number of table entries used within a compile is displayed
           at the end of the output list from the Compiler.

       17. The time needed to compile a program can be reduced by turning
           off the ANTIC chip within the computer. This turns off the
           display to the screen yet gives a fairly significant increase
           to the Atari's internal speed. In a normal Pascal program, you
           can have POKE(559,0) to turn it off and POKE(559,34) to turn
           it back on. But a special compile time option is provided to
           make use of this feature to speed up compiles. It is as
           follows. Have a statement (*$S+*) to turn the ANTIC off
           (increase speed), and use (*$S-*) to turn the ANTIC on (resume
           normal speed). These options may appear anywhere within a
           program. The ANTIC is automatically turned back on at compile
           termination and at time of error (if any).


       Draper Pascal 2.1                                 The Supervisor

                                 The Supervisor

       The Supervisor is a high performance machine language program
       which simulates a pseudo 16-bit stack oriented computer. It
       executes the pseudo code that is generated by the Compiler.

       It is loaded into memory by disk operating system at the hex
       location $1D7C, which is just above DOS in memory. It should work
       with any DOS that allows a program to load at that address, such
       as Atari DOS 2.1S, Atari DOS 2.5, or SpartaDOS version 2.x or
       higher. A message will be displayed if the Supervisor cannot be
       loaded at the proper location.

       The disk filename for the Supervisor's object code is
       'AUTORUN.SYS'. It may be renamed to anything you desire, such as
       'PASCAL.COM', but will not be automatically loaded when the disk
       is booted if the name is other than 'AUTORUN.SYS'. To start the
       Pascal system from the DOS menu, use the 'L', binary load, option
       to load 'AUTORUN.SYS' into memory. Execution will begin

       The Supervisor begins execution by loading and executing the
       Pascal program 'INIT.PCD' from the default drive, which is always
       disk drive 1 immediately after loading the Supervisor. 'INIT.PCD'
       is the name of the main menu program. You may substitute any
       compiled Pascal program of your own by naming it 'INIT.PCD'. In
       this manner, you can have a true turnkey system where your program
       begins execution after booting the disk.

       After termination of each Pascal program, the Supervisor gives you
       a choice of what to do next. You are prompted with the following


       If you press the START key, your Pascal program will execute again
       from the beginning. If you press the SELECT key, control will be
       transfered to the main menu program (INIT.PCD). If you press the
       ESC key, you will exit to the DOS utility menu. You also have two
       other options at this point. They are both used for debugging
       purposes. If you press CTRL-S (the 'S' key while holding down the
       CTRL key), the stack values, at termination time, will be
       displayed. If you press CTRL-T, the internal trace table, if
       active, will be displayed. With either of these two debugging
       options, you will be asked where the display should be sent by the
       prompt 'WHERE? (FILESPEC)'. To see it on the screen, enter 'E:'.
       It also may be sent to printer or disk by following normal
       filespec naming conventions. If the display is sent to the screen,
       you may stop the scrolling by use of the space bar. Press the ESC
       key if you have seen enough and wish to return to the Supervisor
       termination prompt. Any other key causes scrolling to continue as


       Draper Pascal 2.1                             Pascal Definitions

                               Pascal Definitions

       Syntax is shown below for each of the Draper Pascal reserved
       words.  The complete manual provided to registered users, however,
       contains COMPLETE definitions, COMPLETE sample programs
       demonstrating the use of each reserved word, as well as BASIC

       ABS                FUNCTION ABS(Number):INTEGER;

       ADDR               FUNCTION ADDR(Var):INTEGER;


       ARCTAN             FUNCTION ARCTAN(Var):REAL;

       ARRAY              ARRAY[Number1] OF Type
                          ARRAY[Number1,Number2] OF Type

       ASC                FUNCTION ASC(Cvar):INTEGER;


       BLOAD              PROCEDURE BLOAD(Program);


       CALL               PROCEDURE CALL(Address);

       CASE               CASE expr1 OF const1 : stmt1;
                                        const2 : stmt2;
                                        constn : stmtn

                          CASE expr1 OF const1 : stmt1;
                                        const2 : stmt2;
                                        constn : stmtn
                          ELSE stmtx


       CHR                FUNCTION CHR(expr1):CHAR;

       CLOSE              PROCEDURE CLOSE(File);

       COLOR              PROCEDURE COLOR(Number);


       Draper Pascal 2.1                             Pascal Definitions

       CONCAT             PROCEDURE CONCAT(Parm1,Parm2,...):STRING;

       CONST              CONST name1=value1; name2=value2; ...

       COPY               FUNCTION COPY(Source,Index,Length) : STRING;

       COS                FUNCTION COS(Var):REAL;


       DEG                PROCEDURE DEG;

       DELETE             PROCEDURE DELETE(Source,Index,Size);


       DOS                PROCEDURE DOS;

       DRAWTO             PROCEDURE DRAWTO(X,Y);


       DVSTAT             PROCEDURE DVSTAT(A,B,C,D);


       EOF                EOF(File);

       EOLN               EOLN(File);

       EXIT               PROCEDURE EXIT;

       EXP                FUNCTION EXP(Var):REAL;

       EXP10              FUNCTION EXP10(Var):REAL;



       FOR                FOR var := expr1 TO expr2 DO statement;
                          FOR var := expr1 DOWNTO expr2 DO statement;


       GOTOXY             PROCEDURE GOTOXY(X,Y);

       GRAPHICS           PROCEDURE GRAPHICS(Number);

       HIMEM              PROCEDURE HIMEM(Value);


       Draper Pascal 2.1                             Pascal Definitions

       IF                 IF expr1 THEN stmt1;
                          IF expr1 THEN stmt1 ELSE stmt2;

       INSERT             PROCEDURE INSERT(Source,Destination,Index);




       LENGTH             FUNCTION LENGTH(svar):INTEGER;

       LN                 FUNCTION LN(Var):REAL;


       LOCK               PROCEDURE LOCK(Filename);

       LOG                FUNCTION LOG(Var):REAL;

                          FUNCTION LPENV:INTEGER;




       NOTE               PROCEDURE NOTE(Iocbno,Sector,Byte);

       ODD                FUNCTION ODD(iexp);

       OPEN               PROCEDURE OPEN(Fileno,Aux1,Aux2,Filename);;


       OPTIONS            OPTIONS(Opt1,Opt2,...,Optn);


       ORD                FUNCTION ORD(Realvar):INTEGER;

       PADDLE             FUNCTION PADDLE(Number):INTEGER;

       PEEK               FUNCTION PEEK(Address):INTEGER;

       PLOT               PROCEDURE PLOT(X,Y);

       POINT              PROCEDURE POINT(Iocbno,Sector,Byte);


       Draper Pascal 2.1                             Pascal Definitions

       POKE               PROCEDURE POKE(Address,Value);

       POS                FUNCTION POS(Pattern,Source):INTEGER;

       PROCEDURE          PROCEDURE Name;
                          PROCEDURE Name(Parm1,Parm2,...,Parmn);

       PROGRAM            PROGRAM Name;

       PTRIG              FUNCTION PTRIG(Number):INTEGER;

       PURGE              PROCEDURE PURGE(Filespec);


       READ, READLN       PROCEDURE READ(File,Var1,Var2,...Varn);



       REPEAT             REPEAT Stmt1; ... ;Stmtn UNTIL Condition;

       RESET              PROCEDURE RESET(File,Filespec);

       REWRITE            PROCEDURE REWRITE(File,Filespec);

       RND                FUNCTION RND(Iexp):INTEGER;


       SETCOLOR           PROCEDURE SETCOLOR(Register,Hue,Luminance);

       SHL                Expr1 SHL Expr2

       SHR                Expr1 SHR Expr2

       SIN                FUNCTION SIN(Var):REAL;

       SOUND              PROCEDURE SOUND(Voice,Pitch,Distortion,Volume);

       SQR                FUNCTION SQR(Var):REAL;

       SQRT               FUNCTION SQRT(Var):REAL;


       STATUS             PROCEDURE STATUS(Iocbno,Ivar);

       STICK              FUNCTION STICK(Number):INTEGER;


       Draper Pascal 2.1                             Pascal Definitions

       STR                FUNCTION STR(Var):STRING;

       STRIG              FUNCTION STRIG(Number):INTEGER;



                          PROCEDURE TRACEON('Number);


       UNLOCK             PROCEDURE UNLOCK(Filespec);

       VAL                FUNCTION VAL(Svar):INTEGER or REAL;

       VAR                VAR Name1,Name2,...,Namen : Type;
                          VAR Name1,Name2,...,Namen : ARRAY[Number]
                              OF Type;

       WAIT               PROCEDURE WAIT(Number);

       WHILE              WHILE Condition DO Statement;

       WRITE              WRITE(File,Expr1,Expr2,...);

       WRITELN            WRITELN(File,Expr1,Expr2,...);

       XCTL               PROCEDURE XCTL(Filespec);

       XIO                PROCEDURE XIO(Number,File,Aux1,Aux2,Filespec);


       Draper Pascal 2.1                             System Information

                               System Information

       The Supervisor uses zero page locations $A0 - $BF. Locations $80 -
       $9F are available for your use if desired. Various locations
       between $D4 and $FD are used by the floating point routines. Page
       six ($600 - $6FF) is available for your use and not used by the
       Pascal system.

       The Supervisor is loaded into memory by DOS at the address $1D7C.
       If this memory location is not available, then an error message is
       given, along with an explanation of the probable cause of the
       problem. The pseudo code program to be executed is loaded in
       memory immediately after the end of the Supervisor. The pseudo
       machine stack extends from the end of the pseudo code program to
       the MEMTOP position, just before screen memory.

                             Filename Descriptions

       The files named below are included in this ARC file:

       AUTORUN.SYS             Supervisor object code
       COMPILER.PCD            Compiler pcode
       EDITOR.PCD              Editor pcode
       INIT.PCD                Main Menu pcode
       INIT.PAS                Main Menu Pascal source
       EXPLNERR.PCD            Error code explainor (used by Compiler)
       RSVDWRDS.TXT            Reserved word list (used by Compiler)
       ERRORS.TXT              Text for compile errors (used by
       RAMDISK1.DAT            Ramdisk setup (See complete manual)
       RAMDISK2.DAT            Ramdisk setup (See complete manual)
       RAMDISK3.DAT            Ramdisk setup (See complete manual)
       NOTITLE.OBJ             Used to suppress title (See complete
       SAMPLE1.PAS             Kaleidoscope sample program source
       SAMPLE2.PAS             Roman numeral sample program source
       PASCAL.DOC              This introduction manual


       Draper Pascal 2.1                             Reserved Word List

                               Reserved Word List

       ABS      DEG       FUNCTION  ODD       READLN    STRING
       ADDR     DELETE    GOTOXY    OF        REAL      THEN
       AND      DIV       GRAPHICS  OPEN      RECORD    TO
       ARRAY    DOS       IF        OPTIONS   RESET     TRACEON
       ASC      DOWNTO    INSERT    OR        REWRITE   TRUE
       BEGIN    DRAWTO    INTEGER   ORD       RND       UNLOCK
       CALL     ELSE      LENGTH    PLOT      SHL       VAR
       CASE     END       LN        POINT     SHR       WAIT
       CHAR     EOF       LOCATE    POKE      SIN       WHILE
       CHR      EOLN      LOCK      POS       SOUND     WRITE
       CLOSE    EXIT      LOG       PROC      SQR       WRITELN
       COLOR    EXP       LPENH     PROCEDURE SQRT      XCTL
       COPY     FILE      MOD       PURGE     STICK
       COS      FOR       NOT       RAD       STR
       CVTREAL  FUNC      NOTE      READ      STRIG


       Draper Pascal 2.1                                      Operators


       Operator                          Operation
       ________                          _________

         :=                              assignment

         +                               addition
         -                               subtraction
         *                               multiplication
         / or DIV                        division
         MOD                             modulo (remainder after

         =                               equality
         <>                              inequality
         <                               less than
         >                               greater than
         <=                              less than or equal to
         >=                              greater than or equal to



       Draper Pascal 2.1                                 Error Messages

                                 Error Messages

                          COMPILE TIME ERROR MESSAGES

      01: Compiler table overflow (max 170)
      02: Number expected
      03: '=' expected
      04: Identifier expected
      05: Constant type identifier, number, or string constant expected
      06: 'BEGIN' expected
      07: Too many nesting levels
      08: ':' expected
      09: '.' expected
      10: ';' expected
      11: Undeclared identifier
      12: Invalid type of identifier
      13: ':=' expected
      14: 'END' expected
      15: ';', 'ELSE', or 'END' expected
      16: 'THEN' expected
      17: '#' expected
      18: 'DO' expected
      19: '#' or FILE type identifier expected
      20: '[' expected
      21: ']' expected
      22: ')' expected
      23: Illegal factor or identifier type
      24: INCLUDE file nesting too deep
      26: 'OF' expected
      27: Mismatched data types
      28: 'TO' or 'DOWNTO' expected
      29: 'UNTIL' expected
      30: Range error
      31: '(' expected
      32: ',' expected
      33: Literal too long or missing end quote (')
      34: 'END' but no RECORD started
      35: Incorrect number of parameters
      36: INTEGER type identifier expected
      37: STRING type identifier expected
      38: REAL type identifier expected
      39: CHAR type identifier expected
      40: FILE type identifier expected
      41: HEX type identifier expected
      42: STRING constant expected


       Draper Pascal 2.1                                 Error Messages

                         EXECUTION TIME ERROR MESSAGES


                           This message occurs if an attempt is made to
                           store a string array element into an occurance
                           that is higher than defined for the variable.
                           For example, if you tried to store the
                           twentieth entry of an array that was only
                           defined to hold ten occurances, you would get
                           the message. This message only applies to
                           string arrays since other array types are not
                           checked for valid occurance numbers.


                           This message is issued if the list output
                           device you specify in response to the 'WHERE?
                           (FILESPEC)' prompt cannot be opened. The
                           prompt is issued only for the debug features
                           trace and stack display.

       CIO ERROR xxx FOR IOCB # y

                           Some kind of Input-Output operation was
                           performed which resulted in an abnormal return
                           code from the Atari operating system. Refer to
                           your BASIC or DOS manual for the meaning of
                           the error number 'xxx'. 'y' is the IOCB number
                           which the error occured on. Note that this
                           message will not be printed if OPTIONS(0) is
                           in effect. In this case it is your
                           responsibility to check the return code by
                           interrogating IORESULT after each I/O type

       AT OFFSET

                           This message accompanies some other error
                           message and refers to the offset within the
                           pseudo code of the instruction that had the
                           error. Refer to the offset shown on your
                           compile listing to determine the Pascal
                           instruction that experienced the error.


       Draper Pascal 2.1                                 Error Messages


                           This message indicates that execution of the
                           program was stopped because the BREAK key was
                           pressed. The offset of the instruction
                           executing is shown in the 'AT OFFSET' message.
                           Note that this message will not occur (and the
                           program will not stop after BREAK is pressed)
                           if OPTIONS(4) is in effect.


                           This message indicates that an attempt was
                           made to increase the value of the stack
                           pointer to a value which would overlay screen
                           memory or the trace buffer, if the trace was
                           active. It may also be caused by manipulation
                           of a record without sufficient room between
                           the top of the stack and the top of available
                           memory (MEMTOP) to temporarily hold it.


                           This message should not occur. It indicates
                           that a pseudo instruction was encountered
                           which is invalid. If you get this message, it
                           means that your '.PCD' file has been corrupted
                           somehow or an XCTL was made to a file that was
                           not a pseudo code file. To correct, re-compile
                           the program in question. It may also occur if
                           you attempt to run a Draper Pascal program
                           which was compiled under a previous release of
                           this software.


       Draper Pascal 2.1                              Registration Form

                               Registration Form

       When you register for a fee of only $15.00, you will receive a
       copy of the latest version of the Draper Pascal manual.  Also, if
       a later version of the software is more current than the version
       you are registering, you will receive a diskette containing it.
       In addition to all relative information in this manual, the
       complete manual provided to registered users contains the

       *  Complete Draper Pascal reserved word definitions

       *  Complete Draper Pascal example programs demonstrating the use
          of each reserved word

       *  BASIC equivalents for each reserved word, where applicable

       *  Information on setup and use of a Ramdisk for Draper Pascal.
          After proper initialization, the Editor will take less than two
          seconds to load and the Compiler will take less than three
          seconds.  Also, the default drive will be automatically set to
          the Ramdisk.

       *  A royalty-free, non-exclusive license to allow you to
          distribute software developed using Draper Pascal

       *  Complete Draper Pascal source listings for the Editor, Main
          Menu program, Ramdisk initialization program, and sample

       *  Editor command summary

       *  Information on how to suppress the title screen from being

       *  Trace format descriptions

       *  Internal data format descriptions

       *  Notes on printer usage with Draper Pascal

       *  Technical support, by mail, at no charge

       If you purchased Draper Pascal directly from Draper Software in
       your own name, then your copy is already registered and you will
       recieve all the benefits of registration.  You do not need to send
       in a registration form.

       If you received Draper Pascal some other way, you may register
       your copy by filling out the following form and mailing it to the
       listed address along with your check or money order.


       Draper Pascal 2.1                              Registration Form


                      Draper Pascal 2.1 Registration Form

       Mail payment to:      Draper Software
                             307 Forest Grove Drive
                             Richardson, TX 75080-1939

       Texas residents:  Please add 8% tax.

       Note: Please allow three to five weeks for delivery.

       NAME  _________________________________________

       COMPANY (if any) ______________________________

       ADDRESS  ______________________________________

       CITY/STATE  ___________________________________

       ZIP  __________________

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