SpeedStart CP/M-86
| Industry | Software |
|---|---|
| Products | SpeedStart CP/M |
A self-booting disk refers to a floppy disk designed for home computers or personal computers that automatically launches a standalone program upon powering on or rebooting the system. It operates directly on the "bare machine" hardware, bypassing the need to load the computer’s operating system. This approach was prevalent from the late 1970s through the early 1990s, particularly for distributing video game titles.
The phrase "PC booter" denotes self-booting software specifically for IBM PC compatible machines. On platforms such as the Apple II and Atari 8-bit computers, the majority of software was inherently self-booting. Within IBM PC environments, a key difference exists between self-booting applications and those initiated through operating systems like MS-DOS. The label "PC booter" became common following the decline of self-booting games.
Purpose
In certain home computer systems like the Apple II, software is loaded by inserting a floppy disk and then powering on or resetting the device—much like using a cartridge with consoles such as the Atari 2600 or Nintendo Entertainment System. This process removes the requirement for a command-line interface or manual program execution.
Self-booting disks frequently employed unconventional disk formatting techniques to deter viewing or duplication via standard disk operating systems, although some specialized tools could still copy portions of these disks.
Typically, self-booting programs circumvent existing operating systems such as MS-DOS, accessing hardware directly or utilizing low-level routines embedded in read-only memory. Certain programs even offer custom replacements for portions of the OS.
Drawbacks
Using self-booting disks necessitates powering up or rebooting the machine to run software, which restricts multitasking capabilities. Additionally, since the software resides solely on its floppy disk, storage capacity is limited when compared to alternatives like hard disk drives.
These applications cannot readily take advantage of hardware accessed through OS-level device drivers, requiring built-in support for each peripheral device. Consequently, they miss out on improvements from driver updates, bug fixes, or compatibility with newer hardware.
Examples
Between 1983 and 1984, Digital Research released business and educational software for IBM PC distributed on bootable floppy disks bundled with SpeedStart CP/M—a streamlined version of CP/M-86 functioning as a bootable runtime environment.
Infocom launched third-party games for the Macintosh 128K using its proprietary bootable operating system at the time of release.
A simplified variant of GeoWorks Ensemble served as the foundation for America Online’s client software through the late 1990s. AOL was delivered on a single 3.5-inch floppy disk capable of booting GeoWorks directly.
In 1998, Caldera introduced a demonstration version of their 32-bit DPMI web browser and email client, DR-WebSpyder, distributed on a fully self-contained bootable 3.5-inch floppy disk. On 386 PCs equipped with at least 4 MB RAM, this floppy booted a minimal DR-DOS 7.02 environment including memory management, a RAM disk, modem, LAN, mouse, and display drivers, automatically launching the graphical browser without accessing the hard drive. Users could begin browsing immediately after logging in.
See also
Further reading
- Donnie Pinkston, Chapter 3. Project 2: PC Booter, Pintos Projects, Caltech, November 27, 2018. Accessible via Caltech course platform.