IEEE Awards Booklet - 2019 - 14

2019 Ieee medAls

IEEE/RSE James Clerk Maxwell Medal
Sponsored by the Maxwell Medal Fund

David Flynn and David Jaggar
For contributions to the development of novel Reduced Instruction
Set Computer (RISC) architectures adopted in 100 billion+
microprocessor cores worldwide

T

he groundbreaking accomplishments of David Flynn
and David Jaggar while working at Advanced RISC Machines (ARM) during the 1990s created the foundations
that launched the system-on-chip market with microprocessors
that proliferate today's digital devices such as smartphones and
portable computing devices and continue to play an important role in the evolving Internet of Things. Based on reduced
instruction set computing (RISC) processing, their designs use
less energy, making them perfect for battery-powered and fanless devices. Flynn and Jaggar first collaborated on designing
versatile development boards and firmware to enable software
development. Together they defined a new ARM architecture
directed toward embedded control, on-chip debug, and highspeed multiplication for signal processing that resulted in the
ARM7 microprocessor family fundamental to successful embedded control designs. Jaggar developed the Thumb instruction
set architecture to provide substantial code density improvements over processors with single instruction sets, which were
compromised between high-performance and low system cost
and power consumption. Adding Thumb as a second instruction set to the ARM architecture allowed lower cost and power
consumption by utilizing the compressed Thumb instruction
set for the vast majority of code while still allowing peak performance for critical code using the ARM instruction set. This
technique reduced overall code size by 30% and increased performance from low-cost, slower memories by 50%, and was first

used in the ubiquitous ARM7TDMI. Over 100 billion devices
now feature Jaggar's architectural innovation, which has been
particularly successful in mobile phone designs. Flynn then led
the ARM program that evolved this design from a full-custom
transistor layout macrocell to be fully synthesizable to deliver
fast time-to-market intellectual property. Flynn drove the development of the first generation of ARM's Advanced Modular
Bus Architecture (AMBA) that became the on-chip industry's
standard interconnect, which enabled the vast ARM systemon-chip ecosystem by flexibly interfacing the ARM7TDMI to
hundreds of silicon partner's peripheral libraries. Jaggar's Architecture Reference Manual and definitions have allowed partners such as Apple to develop their own ARM implementations while still adhering to a global standard, allowing ARM
to license both specific implementations and the architecture
itself. Flynn's and Jaggar's innovations have changed the shape of
an industry, bringing together systems, software and application
design, electronic design automation, semiconductor foundry,
electronics, and consumer manufacturing companies to work
more successfully and more eﬃciently to further enable the
digital and information revolution around the world.
An IEEE Senior Member, Flynn is a former ARM Fellow residing in Cambridge, UK, and a visiting professor with the University of Southampton, UK.
An IEEE member, Jaggar is a former ARM Fellow currently
residing in Canterbury, New Zealand.

Scope: For groundbreaking contributions that have had an exceptional impact on the development of electronics and electrical
engineering or related fields.
14 | 2019 IEEE awards bookLET
IEEE Awards Booklet - 2019

Table of Contents for the Digital Edition of IEEE Awards Booklet - 2019
