Mark Dean and Dennis Moeller

Industry Standard Architecture System
Computing and Telecommunications

When you plug your printer, keyboard, or monitor into your PC, the majority of the time you'll find that it simply works, no matter what brand your peripherals are or how long ago you purchased them.

This is largely because of the developments of inventors Mark E. Dean and Dennis L. Moeller, who developed the internal architecture of what's know as the ISA (Industry Standard Architecture) at IBM in the early 1980s.

Dean was born on March 2, 1957, in Jefferson City, Tenn. He earned a BS in electrical engineering at the University of Tennessee in 1979, followed by a master's degree in electrical engineering from Florida Atlantic University in 1982.  He later went on to earn a PhD in electrical engineering from Stanford University in 1992. He began working for IBM in 1980.

Moeller was born on April 28, 1950 in St. Louis, Mo. He received BS and MS degrees in electrical engineering from the University of Missouri. In 1974, he joined IBM's semiconductor manufacturing team and later moved on to IBM's Series 1 mini-computer printer project.

The pair began working together on a team tasked with building a microcomputer system with bus connectivity for peripheral processing devices for IBM computers and compatible PCs. A bus is a device that connects a computer's central processing unit with devices such as keyboards, mice, monitors, printers, and the like. A bus allows the devices to communicate with one another, making it possible for devices to work together efficiently and at high speeds.  

Dean and Moeller made architectural improvements within the PC and the bus that laid the foundation for explosive growth in the computing industry. Their invention, for which they received U.S. Patent No. 4,528,626 in 1985, made it possible for users to connect computers to peripherals by simply plugging them in.

IBM first brought the concept to market in 1984 with its PC/AT computer. An augmented version of the ISA bus remains standard within most PCs to this day. Dean and Moeller were inducted into the National Inventors Hall of Fame for their invention in 1997.

Dean continued at IBM and invented numerous other devices related to PC systems, including the world's first one-gigahertz processor chip. He also contributed to the design of IBM's first personal computer, holding three of the nine core patents upon which these machines were based. He holds over 25 patents and has been honored with numerous awards, including election to the National Academy of Engineers, membership in the American Academy of Arts and Science, and awarded the Ronald H. Brown American Innovators Award.

In 1995, Dean became the first African American to ever be named an IBM Fellow. He has held a variety of posts at IBM, including Vice President of Performance for the RS/6000 division, Director of the Austin Research Research Lab, and in 1994, Vice President of the IBM Almaden Research Center in San Jose, Calif. Here, he led an effort to develop tablet-style PCs – magazine-sized devices that would allow users to read text on them much as they would on a newspaper page or in a magazine. Currently, Dean is the John Fisher Distinguished Professor at the University of Tennessee College of Engineering.

Moeller became a senior technical staff member in the IBM Consumer Division. He holds 25 patents related to PC system designs and PC printers.