MAY 2002 CORE 3.2 A PUBLICATION OF THE COMPUTER HISTORY MUSEUM WWW.COMPUTERHISTORY.ORG PAGE 1 May 2002 FUNDAMENTALS IN COREA publication of the Computer History3.2 Museum IN THIS MISSION ISSUE TO PRESERVE AND PRESENT FOR POSTERITY THE CHANGING TIMES ARTIFACTS AND STORIES OF THE INFORMATION AGE INSIDE FRONT COVER VISION FUNDAMENTALS IN CHANGING TIMES TO EXPLORE THE COMPUTING REVOLUTION AND ITS John C Toole IMPACT ON THE HUMAN EXPERIENCE As our fiscal year ends in June, it’s Look carefully at all the activities poses some unique opportunities today, 2 natural to look at the Museum’s reported in this issue, and you will see but also challenges us to project our THE APOLLO GUIDANCE COMPUTER accomplishments and future plans. It is how our organization is growing. The next 10 years very carefully. We also DESIGNING THE AGC also a time to reflect on how amazing free lecture series has been a are getting much more information on EXECUTIVE STAFF Eldon Hall our annual fundraising support has tremendous success. Our curatorial the costs and timelines for our plan of MISSIONS WITH THE AGC been during a difficult year in the U.S. staff is doing an outstanding job in record with NASA, which becomes John C Toole David A Miller David Scott and around the world. Thank you to organizing the collections, focusing on important to our analysis. The “Beta EXECUTIVE DIRECTOR & CEO VICE PRESIDENT OF DEVELOPMENT 2 Karen Mathews Michael R Williams everyone who has contributed to our future exhibits, and working with an Building” that will provide additional EXECUTIVE VICE PRESIDENT HEAD CURATOR 8 expanding programs and enabled us to impressive list of volunteers who are room for us to grow is still a major HISTORY MATTERS Mike Williams grow in stature, capability, and helping as docents, greeters, and priority, but will be delayed several professionalism! It is critically important enthusiastic helpers. We are also months in this calendar year as we PUBLICATION STAFF to operate in the black, and I am happy finding ourselves much more prominent refine our plans. Stay tuned for more 9 Karyn Wolfe RECENT DONATIONS to report that our audited 2001 in the press. Tours of our Visible information. EDITOR financial statements show exactly that. Storage Exhibit Area (with expanded 6 10 With your continued support, we expect Saturday hours twice a month) provide Although, over time, plans and details BOARD OF TRUSTEES BASIC to do the same this year and in the visitor access to our collection and may evolve to meet opportunities and BASIC upcoming fiscal year that starts on demonstrate our emphasis on content to address challenges, the building Leonard J Shustek, Chairman Charles H (Chuck) House Christopher Garcia July 1. in the fulfillment of our mission. Finally, blocks of our organization—the people, VENCRAFT LLC INTEL CONVERGED Sally M Abel COMMUNICATIONS GROUP, OPEN LETTER TO HOBBYISTS the new building architecture team, led the collection, and the mission—are DIALOGIC DIVISION FENWICK & WEST LLP Bill Gates The economy, the war on terrorism, and by EHDD, completed their schematic fundamentally strong and the basis of Dave House David L Anderson THOMAS KURTZ ON BASIC the corresponding impacts on local design phase, and delivered an amazing a great institution. Help us make this ALLEGRO NETWORKS SENDMAIL 10 Interviewed by Dag Spicer climates have been extraordinary set of great ideas for our permanent year the best ever! C Gordon Bell Christine Hughes challenges for all non-profits, but the home. The schematic design phase of MICROSOFT CORPORATION ACHIEVEMENT PLUS 16 Peggy Burke Steve Kirsch Museum has remained strong with your exhibit design will continue through REPORT ON MUSEUM ACTIVITIES 1185 DESIGN PROPEL SOFTWARE CORPORATION help. This is an important testament to early fall. Karen Mathews Lori Crawford John Mashey our base of support, which has helped INFINITY CAPITAL LLC SENSEI PARTNERS LLC this organization through good times While our public presence has continued Andrea Cunningham Ike R Nassi 20 and bad. The mission of preserving the to increase during this economic CITIGATE CUNNINGHAM ALLEGIS CAPITAL 13 ANNUAL DONORS stories and artifacts of the information downturn, the Trustees and staff have Donna Dubinsky Suhas Patil HANDSPRING TUFAN age strikes a fundamental note in many also considered the challenges, 21 David Emerson Bernard L Peuto UPCOMING EVENTS people’s minds, which makes our opportunities, and risks at every stage. CLARENT CORPORATION CONCORD CONSULTING CONTACT INFORMATION JOHN C TOOLE organization solid even in challenging In fact, we have been constantly EXECUTIVE DIRECTOR & CEO Samuel Fuller John William Poduska Sr ANALOG DEVICES ADVANCED VISUAL SYSTEMS times. If you have not already donated evaluating our long-term plans, and ON THE BACK COVER to our annual campaign, please have developed new insights into the Eric Hahn F Grant Saviers MYSTERY ITEMS FROM THE COLLECTION INVENTURES GROUP PRIVATE INVESTOR consider this mission and what we are future. Although it’s too early to publicly Gardner C Hendrie John Shoch BACK trying to accomplish, and become a address any emerging options, we are SIGMA PARTNERS ALLOY VENTURES contributor—we have included an insert continually challenging our assumptions Peter Hirshberg Pierluigi Zappacosta Copyright ©2002, Computer History Museum. All rights in this issue to make it as easy as we search for the best investments GLOSS.COM reserved. The Museum is an independent 501(c)(3) organization, FID #77-0507525. PO Box 367, Moffett as possible. of our resources. The changing economy Field, CA 94035, USA. BOARD OF ADVISORS Computer History Museum Building T12-A Gene Amdahl Burge Jamieson Moffett Field, CA 94035, USA SIGMA PARTNERS William Aspray +1 650 604 2579 COMPUTING RESEARCH Randy Katz +1 650 604 2594 (fax) ASSOCIATION UNIVERSITY OF CALIFORNIA BERKELEY Robert Broderson WWW.COMPUTERHISTORY.ORG UNIVERSITY OF CALIFORNIA David Patterson BERKELEY UNIVERSITY OF CALIFORNIA BERKELEY Paul Ceruzzi Submission guidelines for technical articles can be NATIONAL AIR & SPACE MUSEUM, James N Porter found at www.computerhistory.org/core, or contact the SMITHSONIAN INSTITUTION DISK/TREND editor at [email protected]. Federico Faggin Eric Schmidt SYNAPTICS GOOGLE Cover: Photo and exploded-view diagram of James Gray Stephen L Squires the Apollo Guidance Computer Display MICROSOFT CORPORATION HEWLETT-PACKARD COMPANY Keyboard (DSKY) COMPUTER HISTORY MUSEUM CORE 3.2 PAGE 2 PAGE 3 In effect, navigating in space is the THE same as navigating on Earth. One might take a star sighting with a sextant. That information is put into the computer and from it the state vector, i.e. the position and velocity of the missile at any point of time, is computed. The computer orients the missile such that the change in velocity will cause the state vector to be updated so the APOLLO missile will free-fall into the targeted point. While it is thrusting, the guidance GUIDANCE COMPUTER system must control the attitude of the vehicle, the magnitude of the thrust in the case of the Lunar Excursion Module BY ELDON HALL AND DAVID SCOTT (LEM), and the direction of the thrust in the case of the command and service module. Inside the Apollo capsule DESIGN CONSTRAINTS INTRODUCTION DESIGNING THE AGC digital techniques for the Polaris Initially the need for a very reliable program, resulting in the construction of computer with significant computational BY ELDON HALL The following article is drawn from a a wired-program, special-purpose capacity and speed was clear. The lecture given by Apollo Guidance computer to solve the guidance and design constraints included very limited In the early sixties the so-called mini- Computer (AGC) lead designer Eldon control equations. In 1959 the first size, weight, and power consumption. computer had not emerged and there Hall on June 10, 1982 at The Computer version of this system, called the Mark If the designers had known then what was no commercial computer suitable Museum in Boston. It was first printed 1, flew in a Polaris missile. It was the they learned later, or had a complete for use in the Apollo mission. Most of in The Computer Museum Report in Fall, first ballistic missile flown with an on- set of specifications been available as the technologies that were eventually 1982 and provides some insight into board digital computer providing the might be expected in today’s used in the Apollo computer were ones the development of a major component guidance and control computations. The environment, they would probably have just emerging from research and that allowed “a giant leap for mankind.” computer occupied about four-tenths of concluded that there was no solution development efforts. The “design” was a cubic foot, weighed 26 pounds, and with the technology of the early sixties. mainly a task of fitting the components The Computer History Museum consumed 80 watts. Even before this together in order to meet the mission collection contains several items and first guided flight succeeded, designs Establishing interface requirements was requirements for computational capacity prototypes comprising the AGC, were already being explored that would a monumental task. The astronaut and miniaturization. including logic modules, a DSKY, reduce the size and improve the interface was one of these. In 1962, and rope memory; as well as lecture maintainability of the system. The new computers were not considered user- FROM POLARIS TO APOLLO videotape; photos of the units in use design, eventually designated Mark 2, friendly. Heated debates arose over the Previous aerospace computers greatly and under test; and various paper repeated the architecture and logic nature of the computer displays. One influenced the development of the documents that provide us with design with improvements in circuits faction, which usually included the Assemblers at Raytheon testing and building AGC modules Apollo Guidance Computer.