View source for CBASIC

{{short description|Compiled BASIC programming language for CP/M}}
{{Use mdy dates|date=January 2015}}
{{Infobox programming language
| name = CBASIC
| logo =               <!-- (filename) -->
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| screenshot = [[File:Cbasic.svg|300px]]
| screenshot caption = The workflow of compiler and interpreter
| paradigm =           <!-- or: | paradigms = -->
| family =  
| designer =           <!-- or: | designers = -->
| developer = [[Gordon Eubanks]]         <!-- or: | developers = -->
| released =  {{Start date and age|1976}}
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| latest release date =     <!-- {{start date and age|YYYY|MM|DD|df=yes/no}} -->
| latest preview version = 
| latest preview date =     <!-- {{start date and age|YYYY|MM|DD|df=yes/no}} -->
| typing = 
| scope = 
| programming language = [[PL/M]]
| discontinued =
| platform = 
| operating system = [[CP/M]]
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| file format =        <!-- or: | file formats = -->
| website =            <!-- {{url|www.example.com}} -->
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}}
'''CBASIC''' is a [[compiled]] version of the [[BASIC]] [[programming language]] written for the [[CP/M]] [[operating system]] by [[Gordon Eubanks]] in 1976–1977. It is an enhanced version of '''BASIC-E'''.<ref name="Shustek_2016"/><ref name="Kildall_1993"/>

==History==
BASIC-E was Eubank's master's thesis project.<ref name="Shustek_2016"/><ref name="Kildall_1993"/>  It was developed in [[PL/M]] by Eubanks for [[Gary Kildall]]'s new CP/M operating system while both men were at the [[Naval Postgraduate School]] in [[Monterey, California]].<ref name="Shustek_2016"/><ref name="Kildall_1993"/>  BASIC-E was based on a BASIC compiler originally written by Gary Kildall in 1974.<ref name="Shustek_2016"/><ref name="Kildall_1993"/>

Because it was developed at public expense, BASIC-E is in the [[public domain]] and cannot be marketed exclusively.<ref name="Shustek_2016"/><ref name="Kildall_1993"/><ref>[http://www.retroarchive.org/cpm/cdrom/SIMTEL/CPMUG/00README.TXT CPM User Group] The source code can be found on Volume 30</ref> [[Seymour Rubinstein]], the marketing director of [[IMSAI]] contacted Eubanks and asked him to create a saleable version under contract for the [[IMSAI 8080]] [[microcomputer]].<ref>[http://www.cwheroes.org/archives/histories/Eubanks.pdf Gordon Eubanks oral history transcript] {{webarchive|url=https://web.archive.org/web/20060824083542/http://www.cwheroes.org/archives/histories/Eubanks.pdf |date=August 24, 2006 }} p. 9, November 2000, Computerworld Honors Program</ref> Eubanks developed CBASIC in his spare time while he was still a naval officer stationed on the submarine [[USS George Washington (SSBN-598)|USS ''George Washington'']] at [[Vallejo, California]]. He retained joint ownership of the program with IMSAI, and sold '''CB80''' through his own company, ''[[Compiler Systems (company)|Compiler Systems]]'' until it was acquired by [[Digital Research]]{{r|pournelle198205}}<ref name="Shustek_2016"/><ref name="Kildall_1993"/> in 1981.

* CBASIC COMPILER VER 2.07
* CRUN VER 2.38 / COPYRIGHT 1981 COMPILER SYSTEMS INC.

==Features==
BASIC-E and early versions of CBASIC compiled [[source code]] into an intermediate [[p-code machine|p-code]] file, which was then executed by a separate [[run-time system|run-time]] interpreter program. CBASIC could execute in a minimum of 24&nbsp;KB of memory.  Line numbers in the program source were optional, unless needed as a label for a program jump. CBASIC proved very popular because it incorporated 14-digit [[binary-coded decimal]] (BCD) math which eliminated [[MBASIC]]'s rounding errors that were sometimes troublesome for [[accounting]].

CBASIC2 adds the following features:

* Integer variables
* Chaining with common variables
* Additional pre-defined functions
* [[Cross reference]] capability

==Reception==
''[[InfoWorld]]'' in 1980 described CBASIC as the "primary language for the development of commercial CP/M applications", because of developers' widespread familiarity with BASIC and ability to distribute royalty-free binaries without source code to CBASIC owners. The magazine stated that the language had become popular "despite serious drawbacks", including the required [[preprocessor]] for interpreted source code making debugging difficult, slow speed, and incompatible changes.<ref name="iw19800818">{{Cite magazine |date=18 August 1980 |title=Editorial |url=https://books.google.com/books?id=az4EAAAAMBAJ&pg=PT47 |magazine=[[InfoWorld]] |volume=2 |number=15 |page=8}}</ref> Despite noting "irritants", [[Jerry Pournelle]] in December 1980 praised CBASIC's design and documentation. He said that [[BASCOM (Microsoft)|BASCOM]] produced much faster binaries without CBASIC's awkward edit-compile-run-debug loop, however.<ref name="pournelle198012">{{Cite magazine |last=Pournelle |first=Jerry |date=December 1980 |title=BASIC, Computer Languages, and Computer Adventures |url=https://archive.org/stream/byte-magazine-1980-12/1980_12_BYTE_05-12_Adventure#page/n223/mode/2up |access-date=October 18, 2013 |magazine=Byte |page=222}}</ref> In May 1982 he said that "advantages abound" in CB80 compared to BASCOM, such as the ability to redimension arrays, and superior [[garbage collection (computer science)|garbage collection]]. Pournelle assured readers that the documentation was far superior to the usual Digital Research manuals. He denounced, however, the $2000 annual fee to sell software using CB80 as "sheer madness".<ref name="pournelle198205">{{Cite magazine |last=Pournelle |first=Jerry |date=May 1982 |title=Supercalc, Spelling Programs, BASIC Compilers, and Home-Grown Accounting |url=https://archive.org/details/eu_BYTE-1982-05_OCR/page/n227/mode/1up?view=theater |access-date=2024-12-28 |magazine=BYTE |page=226}}</ref> In September 1982 Pournelle said that CB80 "remains a real competitor to [[Pascal (language)|Pascal]] and [[PL/I]] [with] few of the inherent defects of BASIC", citing its [[local variable]]s and Pascal-like [[function (computer science)|function]]s, and approved of its new, freer licensing.<ref name="pournelle198209">{{Cite magazine |last=Pournelle |first=Jerry |date=September 1982 |title=Letters, Pascal, CB/80, and Cardfile |url=https://archive.org/details/byte-magazine-1982-09/page/n314/mode/1up?view=theater |access-date=2024-12-30 |magazine=BYTE |pages=318-341}}</ref> He said in May 1983 that Digital Research had "practically ruin[ed]" Eubanks' CBASIC manual after acquiring his company, but that the new edition was much better.<ref name="pournelle198305">{{Cite magazine |last=Pournelle |first=Jerry |author-link=Jerry Pournelle |date=May 1983 |title=Ulterior Motives, Lobo, Buying Your First Computer, JRT Update |url=https://archive.org/stream/byte-magazine-1983-05/1983_05_BYTE_08-05_The_Electronic_Office#page/n299/mode/2up |magazine=[[Byte (magazine)|BYTE]] |pages=298–324 |volume=8 |issue=5}}</ref>

==References==
{{Reflist|refs=
<ref name="Shustek_2016">{{cite web |url=http://www.computerhistory.org/atchm/in-his-own-words-gary-kildall/ |title=In His Own Words: Gary Kildall |author-first=Len |author-last=Shustek |date=2016-08-02 |work=Remarkable People |publisher=[[Computer History Museum]]}}</ref>
<ref name="Kildall_1993">{{cite web |orig-year=1993 |date=2016-08-02 |title=Computer Connections: People, Places, and Events in the Evolution of the Personal Computer Industry |author-first=Gary Arlen |author-last=Kildall |author-link=Gary Kildall |editor-first1=Scott |editor-last1=Kildall |editor-link=Scott Kildall |editor-first2=Kristin |editor-last2=Kildall |publisher=Kildall Family |type=Manuscript, part 1 |url=http://www.computerhistory.org/atchm/computer-history-museum-license-agreement-for-the-kildall-manuscript/ |access-date=2016-11-17}}<!-- https://web.archive.org/web/20161117231531/http://www.computerhistory.org/atchm/computer-history-museum-license-agreement-for-the-kildall-manuscript/ http://s3data.computerhistory.org/kildall-p.1-78-publishable-lowres.pdf https://web.archive.org/web/20161117232745/http://s3data.computerhistory.org/kildall-p.1-78-publishable-lowres.pdf |archive-date=2016-11-17 --></ref>
}}

==External links==
* [https://web.archive.org/web/20060824083542/http://www.cwheroes.org/archives/histories/Eubanks.pdf Gordon Eubanks own story] of BASIC-E and CBASIC, Computer World oral history transcript, November 2000
* [http://www.znode51.de/pcwworld/l105/user_0/basicman.txt BASIC-E Reference Manual] (December 1976)
* [http://www.cpm.z80.de/manuals/cbasic-m.pdf CBASIC 2 Reference Manual] (Table of contents on p.&nbsp;115) November 1981
* [http://www.vannattabros.com/history3.html Another CBASIC description]
* {{webarchive |url=https://web.archive.org/web/20060504011043/http://www.computergenome.com/blastfromthepast/CBasic.asp |date=May 4, 2006 |title=Alternate CBASIC history}}
<!-- *[http://www.minnow.com/cbasic/chistory.html MB86 – a CBASIC to C converter] broken -->
* [http://people.freebsd.org/~julian/ cbc – a CBASIC to C converter]
* [http://www.z80.eu/dos65.html Interpreter in 6502 assembler]
* [http://newsgroups.derkeiler.com/Archive/Comp/comp.os.cpm/2005-09/msg00146.html CBASIC 2.8 = CBASIC-86 1.00] {{Webarchive|url=https://web.archive.org/web/20160304204355/http://newsgroups.derkeiler.com/Archive/Comp/comp.os.cpm/2005-09/msg00146.html |date=March 4, 2016 }} Posting by Emmanuel Roche

{{BASIC}}
{{Digital Research}}
{{Authority control}}

[[Category:BASIC interpreters]]<!-- was originally "compiled" into bytecode like other BASIC interpreters -->
[[Category:BASIC compilers]]<!-- eventually had a real compiler for it -->
[[Category:CP/M software]]
[[Category:Programming languages created in 1977]]
[[Category:BASIC programming language family]]