David Bradley (engineer)
David J. Bradley | |
|---|---|
| Born | January 4, 1949 |
| Education | B.E.E., University of Dayton (1971); M.S., Purdue University (1972); Ph.D., Purdue University (1975) |
| Occupation(s) | Electrical engineer, computer architect, author, professor |
| Years active | 1975–2004 |
| Known for | Developing the IBM PC ROM BIOS; inventing the Control-Alt-Delete keyboard shortcut |
David J. Bradley (born January 4, 1949) is recognized as one of the twelve engineers responsible for creating the initial IBM PC, most notably for developing its ROM BIOS firmware. He is also acknowledged for inventing the "Control-Alt-Delete" (Ctrl-Alt-Del) keyboard shortcut used to restart the system. Bradley began his career at IBM in 1975 after completing a PhD in electrical engineering at Purdue University, where his research concentrated on computer architecture.
Education
Bachelor of Electrical Engineering, University of Dayton (Ohio), 1971. Master of Science in Electrical Engineering, Purdue University, 1972. Doctorate in Electrical Engineering, Purdue University, 1975.
Control-Alt-Delete
The Control-Alt-Delete key combination was created by Bradley to allow developers and technical writers to reboot the computer without powering it off, thus saving time and reducing wear on components such as the power supply and hard disk. Together with Mel Hallerman, he chose this particular key sequence because it was highly unlikely to be pressed unintentionally on the original IBM PC keyboard.
Although originally designed for internal use, this key combination was documented in IBM’s technical manuals and eventually gained widespread recognition. At the IBM PC’s 20th anniversary in 2001, Bradley credited Bill Gates with popularizing the shortcut: "I may have invented it [Control-Alt-Delete], but I think Bill made it famous."
Precedents for multi-key reboot commands existed prior to this: Exidy’s 1978 Sorcerer Z80 computer required pressing multiple Reset buttons simultaneously, and Videx’s 1980 VideoTerm card for Apple II implemented a Control-Reset combination to reboot the system—both innovations that were well received during their time.
Other accomplishments
Bradley is the author of Assembly Language Programming for the IBM Personal Computer (Simon & Schuster, January 1984), which has been translated into French, Russian, and Bulgarian.
He holds seven patents registered in the United States.
Bradley has held adjunct professorships in electrical and computer engineering at both Florida Atlantic University and North Carolina State University.
Much of his professional tenure was spent at IBM. After earning his B.E.E. from the University of Dayton in 1971 and completing his M.S. (1972) and Ph.D. (1975) at Purdue University, he joined IBM’s Boca Raton facility as a senior associate engineer. There, he contributed to the IBM Series/1 system and later developed the input/output system for the IBM System/23 Datamaster.
In 1980, Bradley was part of a team of twelve engineers who developed IBM’s first Personal Computer, where he created the ROM BIOS. He advanced to lead BIOS and diagnostics development for the IBM PC/XT. In 1983, he established the Personal Systems Architecture Department and played a key role in managing development of the Personal System/2 Model 30 released in 1984.
By November 1987, Bradley was overseeing advanced processor design projects including the development of the 486/25 Power Platform as well as PS/2 Models 90 and 95. In 1991, he assumed responsibility as systems architecture manager for Entry Systems Technology and then became architecture manager for a personal computer initiative employing the PowerPC RISC microprocessor in 1992.
He returned to manage PC group architecture in 1993.
Bradley retired from IBM on January 30, 2004.
He recounted the development process of the IBM PC and shared insights about Control-Alt-Delete in an article published by IEEE's Computer magazine in August 2011.