The DOS Wedge is a piece of

Commodore 64 The Commodore 64, also known as the C64, is an 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 the Guinness ...

system software that was popular in its time. It was written by Bob Fairbairn, and was included by Commodore (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 * Keyword (Internet search), a word or phrase typically used by bloggers or online content creator to rank a web page on a particular topic * Index term, a term used as a keyword to documents in an information syste ...

shortcuts. The DOS Wedge became somewhat of a

de facto ''De facto'' ( ; , "in fact") describes practices that exist in reality, whether or not they are officially recognized by laws or other formal norms. It is commonly used to refer to what happens in practice, in contrast with ''de jure'' ("by la ...

standard, with third party vendors such as Epyx often incorporating identical commands into fastloader cartridges and other Commodore 64 expansion devices. '' COMPUTE!'s Gazette'' published several type-in 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

assembly language In computer programming, assembly language (or 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 be ...

. 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 or subroutine is a sequence of program instructions that performs a specific task, packaged as a unit. This unit can then be used in programs wherever that particular task should be performed. Functions may ...

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. {{aligned table, cols=2, col1header=on, col1class=monospaced, col1align=left, class=wikitable , /''filename'' , Load a BASIC program into RAM , %''filename'' , Load a machine language program into RAM , ↑''filename'' , Load a BASIC program into RAM and then automatically run it , ←''filename'' , Save a BASIC program to disk , @ , Display (and clear) the disk drive status , @$ , Display the disk directory without overwriting the BASIC program in memory , @''command'' , Execute a disk drive command (e.g. {{mono, S0:''filename'', V0:, I0:) , @Q , Deactivate the DOS Wedge

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
- Jim Butterfield, '' COMPUTE!'', October 1983.
DOS Wedge documentation (MS Word format)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