The DOS Wedge is a piece of

Commodore 64 The Commodore 64, also known as the C64, is an 8-bit computing, 8-bit home computer introduced in January 1982 by Commodore International (first shown at the Consumer Electronics Show, January 7–10, 1982, in Las Vegas). It has been listed in ...

system software System software is software designed to provide a platform for other software. An example of system software is an operating system (OS) (like macOS, Linux, Android, and Microsoft Windows). Application software is software that allows users to d ...

that was popular in its time. It was written by Bob Fairbairn, and was included by

Commodore Commodore may refer to: Ranks * Commodore (rank), a naval rank ** Commodore (Royal Navy), in the United Kingdom ** Commodore (India), in India ** Commodore (United States) ** Commodore (Canada) ** Commodore (Finland) ** Commodore (Germany) or ' ...

(CBM) on the 1541 disk drive Test/Demo Disk (filename: "DOS 5.1") and also packaged with the C64 Macro Assembler (filename: "DOS WEDGE64"). The DOS Wedge was referred to in the 1541 drive manual as DOS Support and on the software startup screen as DOS MANAGER. The original design was developed by Bill Seiler. The Wedge made disk operations in BASIC 2.0 significantly easier by introducing several

keyword Keyword may refer to: Computing * Index term, a term used as a keyword to documents in an information system such as a catalog or a search engine * Keyword (Internet search), a word or phrase typically used by bloggers or online content creator to ...

shortcuts. The DOS Wedge became somewhat of a de facto standard, with third-party vendors such as

Epyx Epyx, Inc. was a video game developer and video game publisher active in the late 1970s and 1980s. The company was founded in 1978 as Automated Simulations by Jim Connelley and Jon Freeman, publishing a series of tactical combat games. The Epyx ...

often incorporating identical commands into fastloader cartridges and other Commodore 64 expansion devices. '' COMPUTE!'s Gazette'' published several

type-in Type in may refer to * Type-In, a meeting of typewriter enthusiasts *Type-in program *Type-in traffic Type-in traffic is a term describing visitors landing at a web site by entering a keyword or phrase (with no spaces or in place of a space) in t ...

variations on the DOS Wedge, including a C128 version in its February 1987 issue (see External links, below). The original Commodore DOS Wedge was a 1- KB program written in

MOS 6502 The MOS Technology 6502 (typically pronounced "sixty-five-oh-two" or "six-five-oh-two") William Mensch and the moderator both pronounce the 6502 microprocessor as ''"sixty-five-oh-two"''. is an 8-bit microprocessor that was designed by a small ...

assembly language In computing, assembly language (alternatively assembler language or symbolic machine code), often referred to simply as assembly and commonly abbreviated as ASM or asm, is any low-level programming language with a very strong correspondence bet ...

. It resided in the otherwise unused memory block $CC00–$CFFF (52224–53247) and worked by altering BASIC's "CHRGET"

subroutine In computer programming, a function (also procedure, method, subroutine, routine, or subprogram) is a callable unit of software logic that has a well-defined interface and behavior and can be invoked multiple times. Callable units provide a ...

at $0073 (115) so that each character passing by the BASIC interpreter would be checked for wedge commands, and the associated "wedged-in" routines run if needed.

DOS Wedge functions

Any command that contains an symbol may substitute instead, if desired.

References

*CBM Professional Computer Division (1982). ''Commodore 64 Macro Assembler Development System Manual''. West Chester, PA: Commodore Business Machines. Chapter 5.0. Additional BASIC Disk Commands.

External links

Commodore DOS Wedges: An Overview
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Jim Butterfield Frank James Butterfield (14 February 1936 – 29 June 2007), was a Canadian computer programmer, author, and television personality known for his work with early microcomputers. He is particularly noted for associations with Commodore Business M ...

, ''

COMPUTE! ''Compute!'' (), often stylized as ''COMPUTE!'', is an American home computer magazine that was published from 1979 to 1994. Its origins can be traced to 1978 in Len Lindsay's ''PET Gazette'', one of the first magazines for the Commodore PET. ...

'', October 1983.
DOS Wedge documentation (MS Word format)
{{Webarchive, url=https://web.archive.org/web/20060505164031/http://artofhacking.com/IET/C-64/DOSWEDGE.DOC , date=2006-05-05
Commodore 64 Macro Assembler Development System Manual''COMPUTE!'s Gazette'' February 1987 issue: "DOS Wedge 128" (Part A)(Part B)Commodore Disk Loading BasicsCommodore 1541 Drive Manual (ZIPped text file)
Commodore 64 software Command shells Assembly language software

DOS Wedge functions

See also

References

External links