DOS Wedge


The DOS Wedge was a popular piece of Commodore 64 system software. Written by Bob Fairbairn, it was included by Commodore on the 1541 disk drive Test/Demo Disk and also packaged with the C64 Macro Assembler. 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 shortcuts. The DOS Wedge became somewhat of a de facto 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.
The original Commodore DOS Wedge was a 1-KB program written in MOS 6502 assembly language. It resided in the otherwise unused memory block $CC00-$CFFF and worked by altering BASIC's "CHRGET" subroutine at $0073 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.