Blue Label Software Pascal -> Compas Pascal -> Poly Pascal -> Turbo Pascal v1.0

Posted by on in Blogs
The roots of Turbo Pascal v1.0 started in Denmark.  The first step, in 1981, was the Blue Label Software Pascal Compiler - BLS Pascal Compiler v1.2, copyright 1981 by Poly-Data microcenter ApS, Strandboulvarden 63, DK 2100 Copenhagen - written by Anders Hejlsberg for the NASCOM kit computer.

BLS Pascal was a 12k Pascal language subset compiler created for the British NASCOM Z-80 cassette-based kit computer.  The compiler included an on-screen editor, commands for loading/saving programs from/to cassette tape, the first compile error takes you to the line of source code.  The system also included a "Find" command to take you from an address in the object code to the source line in the program text.  The compiler was available in cassette tape and EPROM versions.  At 12k in size, the compiler supported most of the Pascal language except user definable types, sets, and file types.  Integers were 16-bits, Reals were implemented with 11.5 significant digits.  The compiler also supported linking to external machine code functions and procedures.

The implementation size breakdown for the 12k compiler was: Compiler - 5.5k, On-Screen editor - 1.5k, Runtime library - 4.5k, and Control program 0.5k.  The User and Programming Language manual is available for download at

The second step was Compas Pascal in 1982.  Anders rewrote the BLS Pascal compiler for CP/M and MS-DOS.  It was marketed as Compas Pascal by his Danish company, Poly-Data microcenter.

The third step - Poly Pascal, a command-line compiler, for CP/M-80 released by Anders Hejlsberg by his Danish company, Poly-Data microcenter. The compiler was a complete implementation of the Jensen-Wirth Pascal language.

The final step in November 1983 - Turbo Pascal v1.0 is created for Borland International, Inc.  Distributed on a single floppy disk, Turbo Pascal integrated the Pascal compiler, Wordstar-like text editor, runtime library, run in memory, and creation of .COM programs - all within 131,297 bytes in the TURBO.COM file. The whole product was 33k bytes in size and ran in 64k bytes of memory. The product was delivered for CP/M-80 (Z/80, 5.25 and 8 inch floppy disks), CP/M-86, and MS-DOS/PC-DOS.  The product was released November 20, 1983 and was priced at $49.95.  Turbo Pascal disk was not copy protected. The software came with a "Book License": "You must treat this software just like a book ... may be used by any number of people ... may be freely moved from one computer location to another".

Gold User, Rank: 1, Points: 2466
David Intersimone (known to many as David I.) is a passionate and innovative software industry veteran-often referred to as a developer icon-who extols and educates the world on Embarcadero developer tools. He shares his visions as an active member of the industry speaking circuit and is tapped as an expert source by the media. He is a long-standing champion of architects, developers and database professionals and works to ensure that their needs are folded into Embarcadero's strategic product plans. David holds a bachelor's degree in computer science from California Polytechnic State University at San Luis Obispo, California.


  • Guest
    Lars D Sunday, 2 November 2008

    Good sip :-)

  • Guest
    ahmoy Sunday, 2 November 2008

    and the first Turbo Pascal was written using what language?

  • Guest
    Chee Yang Chau Sunday, 2 November 2008

    It was a great movement for pascal history. But shall we keep focus on the pass history achievement or we should be more focus on the future of Delphi where the Delphi will head to?

  • Guest
    Hallvard Vassbotn Sunday, 2 November 2008

    ahmoy: I think it is a safe bet to say that Turbo Pascal was written in assembly - at least the compiler part.

  • Guest
    davidi Monday, 3 November 2008

    Here are the file sizes for Turbo Pascal version 1.0 from the floppy disk: - 33,280 bytes
    Turbomsg.ovr - 1,408 byte

  • Guest
    davidi Monday, 3 November 2008

    Turbo Pascal version 1.0 was definitely written in Assembler!

  • Guest
    davidi Monday, 3 November 2008

    Chee Yang Chau - we are definitely still moving Delphi forward. The roadmap is public and will be updated soon (according to Nick Hodges). It is okay to celebrate Turbo Pascal. While I am having fun doing this, I am also focused on our recently release Delphi 2009 native code compiler product.

    What is on your list of where Delphi needs to head to?

  • Guest
    Anders Monday, 3 November 2008

    PolyPascal was not a command line compiler. It had a simple IDE with a command based shell and a WordStar compatible editor. These are the command it supported:

    LOAD Load source from disk.
    SAVE Save source to disk.
    NAME Display/edit current filename.
    EDIT Edit source.
    WHERE Resume editor.
    COMPILE Compile source.
    RUN Execute compiled program.
    PROGRAM Link program.
    OBJECT Compile to object file.
    FIND Find position of run-time error in source.
    DIR Display disk directory.
    USE Display/edit autodisk/user.
    MEMORY Display mememory parameters.
    ZAP Delete source.
    HELP Display help.
    QUIT Return to MS-DOS.

    I haven't got a copy of Compas Pascal anymore, but AFAIR it too had an IDE.

  • Please login first in order for you to submit comments
  • Page :
  • 1

Check out more tips and tricks in this development video: