Text preview for : Engineering_Response_to_the_Star_LSI_Workstation_Goals_Ver_2.0_May79.pdf part of xerox Engineering Response to the Star LSI Workstation Goals Ver 2.0 May79 xerox sdd memos_1979 Engineering_Response_to_the_Star_LSI_Workstation_Goals_Ver_2.0_May79.pdf



Back to : Engineering_Response_to_t | Home

Engineering Response to the
Star LSI Workstation Goals

Version 2.0
May 1979

The Star LSI Workstation Goals document sets guidelines for the implementation of a low
cost workstation (terminal, processor, and peripherals) for the OIS Star product. This
document responds to those goals.

Version 2.0 represents current thinking concerning the design of the Star LSI Workstation.
The reader is encouraged to send comments to Bob Belleville (Belleville @ ParcMaxc or
8*923*4520). This file is stored on [I.RIS] (Wortstation) LsiWS 2.0 ) LsiWS.press.




Prepared by Robert L. Belleville
SDD Workstation Design



Approved by Ed Miller
SDD System Design and Test



Approved by Hal LaZar
SDD Technical Program Office



Approved by David E. Liddle
SDD

XEROX
Systems Development Department
3408 Hillview Avenue
Palo Alto, California 94304



This document is Xerox Private Data.
Engineering Response to the Star LSI Workstation Goals - May 1979

Table of Contents

1. Introduction 1

2. Mandatory References 1

3. Informational References 2

4. General Requirements 3

5. System Concepts 4

6. Workstation Configuration 6

7. UMC Estimate 9

8. Performance/Physical Characteristics 9

9. Graphic Output 9

10. IMO 9

11. Cost of Ownership 9
Engineering Response to the Star LSI Workstation Goals - May 1979 1


Engineering Response to the
Star LSI Workstation Goals
1. Introduction, Conclusions, and Recomendations'
The Star LSI Workstation Goals document [reference 1) sets guidelines for the implementation of a
low cost workstation (terminal, processor, and peripherals) for the OIS Star product. This document
responds to those goals.

Between October 1978 and April 1979 a number of studies have been conducted to determine the
most appropiate implementation for the workstation.

The October study, reference (10), made a broad investigation of possible design approaches. In
addition, this study carefully evaluated a synchronous design approach, developed by Butler
Lampson (PARC) reference (2), in view of the goals. The recomendation of the October study was
to pursue the synchronous approach.

During January and February of 1979 additional investigations were made to understand the nature
of the synchronous approach and to further refine the design approach. (references [11-24).)

A workable approach, named Dandelion, evolved from the combination of the PARe processor
design, an independent display controller, an independent 8085 based low speed 1/0 subsystem, and
an expanded memory system. This approach most nearly meets the three most important goals -
Star functionality, 1981 IMO, and cost.

A number of changes have occured since the Goals were written. The most important is the
development of a ROSIMohawk base LSEP which can be connected to Dandelion. The full page
display and quarter page display have been replaced by the 17" large format display and the Data
Terminal "B" respectively.

This document parallels the Goals as closely as possible. The reader is urged to refer to the Goals
while reading this Response.

2. Mandatory References
[1) Ruebel, R. et. al., Star LSI Workstation Goals, Xerox Internal Memo, 11 September 1977.
Engineering Response to the Star LSI Workstation Goals - May 1979 2


3. Informational References
These background references provides more depth on many of the subjects covered in this
document.

[2] Lampson, B. W., Wildflower Manual (Draft), Xerox Palo Alto Research Center, 18 August
1978. Filed on [IVY] WFManual.Press and [IVY] WFDrawings.Press.

[3] The OIS Processor Principles of Operation, Systems Development Department, April.9, 1977.

[4] ALTO: A Personal Computer System Hardware Manual, Xerox Palo Alto Research Center,
February 1978.

[5] DO Processor Functional Specijicaton, Electronic Operations Department, January 16, 1978.

[6] Ogus, Roy C., Xerox Wire Specification, Systems Development Department, AprilS, 1978.

[7] Microprocessor Data Manual II, Electronic Design 21, October 11, 1978.
[8] Crane, R. C., Star Grounding, Systems Development Department, September 13, 1978.

[9] Wick, J., DO Timing Simulation, Systems Development Department, October 18, 1978.
[10] Belleville, R. et al., A Response to the Star LSI Workstation Goals, Systems Development
Department, November 3, 1978.
[11] Snow, R., Experience with MIDAS, Systems Development Department (Memo), January 3,
1979. Filed on [IRIS] Snow> Midas.memo
Note: References [12, 13, 14, 15, 16, 17, 18, 19, 20, 22, 23, 24] are contained in a single
printable file [IRIS] Notes> WS-Summary.press (62 pages).
[12] Belleville, R., Using a Microprocessor As An Emulator, Systems Development Department
(Memo), January 9, 1979. Filed on [IRIS] Notes> MicroEmulator.memo
[13] Belleville, R., Workstation Processor Performance Requirements, Systems Development
Department (Memo), January 10, 1979. Filed on [IRIS] Notes>
wskipneeds.memo
[14] Charnley, D and R. Snow, Workstation Tools, Systems Development Department (Memo),
January 17, 1979. Filed on [IRIS] Tools> Justification.memo
[15] Ogus, R and S. Purcell, NoteTaker and Workstation, Systems Development Department
(Memo), January 24, 1979. Filed on [IRIS] Notes> NoteTaker.memo
[16] Crane, R., Monitor Characteristics, Systems Development Department (Memo), January 26,
1979. Filed on [IRIS] MonChar.press
[17] Crane, R., Low Speed Printer Interface, Systems Development Department (Memo), January
27, 1979. Filed on [IRIS] LSEP.press
[18] Crane, R., Workstation Display, Systems Development Department (Memo), February 8, 1979.
Filed on [IRIS] Notes> WSDisplay.press
[19] Purcell, S., Sumit Flexibility, Systems Development Department (Memo), February 1, 1979.
Filed on [IRIS] Notes> Flexibility.memo
[20] Purcell, S., Low Speed Electronic Printing and Sumit Workstation, Systems Development
Department (Memo), December 1, 1978. Filed on [IRIS] Notes> LSEP-
Engineering Response to the Star LSI Workstation Goals - May 1979 3


WS.memo
[21] Fairbairn, D., NoteTaker System Manual, Palo Alto olffesearch Center/SSL, December 1979.
(Note: logic drawings also available)
[22] Ogus, R., Workstation Lo~Speed Processor, Systems Development Department (Memo),
February 6, 1979. [IRIS] Notes> LSProc.memo
[23] Crane, R., 64K Memory Reliability, Systems Development Department (Memo), February 9,
1979. Filed on [IRIS] Notes> WSMemRe1.press
[24] Gamer, R., ALU Timing, Systems Development Department (Memo), February 15, 1979.
Filed on [IRIS] Notes> ALUTiming.press
[25] Miller, E. and R. Belleville, Workstation Structure, Systems Development Department
(Memo), February 23, 1979. Filed on [IRIS] Notes> WS-StudyILMemo
[26] Crane, R., Dandelion Memory System, Systems Development Department (Memo), April 9,
1979. Filed on [IRIS] Notes> WSMemSys.press
[27] Hruschak, 1. and S. Marshall, Star/Mohawk control interface, M&OED/SI/IOT (Memo), April
30, 1979.
[28] Belleville, R., Workstation RS-232-C DCE Interface Specification, Systems Development
Department (Memo), May 22, 1979. Filed on [IRIS] RS-232> RS-232-C-DCE-
Spec.memo

4. General Requirements
The Goals[l] require the following general considerations:
1. The Workstation is a multinational product. It is designed to adhere to Multinational
Standards 1-8. It is assumed that the program will be single point design and single
point manufacture.
2. . The Workstation is designed to meet the Star Product Functions Specification for
release 1 as well as releases 2 and 3.

An additional goal is to use standard peripherals developed by Xerox OEM suppliers and other
programs.
Engineering Response to the Star LSI Workstation Goals - May 1979 4



5. System Concepts
The system combines both a high performance processor, developed at the Palo Alto Research
Center, a low cost "off the shelf' LSI microprocessor, and standard peripherals to produce a cost
effective solution to the problems presented by Star application software.

The Dandelion processor must:
a. Support the OIS software language - Mesa.
b. Drive a crt display with more than a full page of multi-font text and graphics.
c. Interface with high performance peripherals such as the 10 million bit per second Xerox
Wire communication network.
d. Support a range of slow devices such as keyboard, pointer, floppy disk, and serial
communication.

To meet these needs, Dandelion is designed from four subystems shown in the diagram.

The central processor section is specially designed from commercially available, high performance,
bit-slice, microprocessor components. It executes Mesa programs and directly interfaces to the rigid
disk, Xerox Wire, and the Low Speed Electronic Printer (LSEP).

Because the image on the crt is large (1024 dots wide by 809 dots high) and must be refreshed
nearly 40 times a second to produce a flicker free image, a separate display controller is included to
send 50 million bits per second from the display memory to the crt.

The memory system, which is designed from LSI memory components, provides the system with
128K words (16 bits wide) of main memory. Error correction for single bit errors is fully automatic.
(K=1024)

To interface to a several slow devices, an Input/Output Processor (lOP) is included. The processor
is an Intel 8085 which is currently used in several Xerox products. LSI controllers connect directly
to the 8085 to dramatically reduce the cost and complexity of the whole system.

Standard peripheral devices are used to the greatest extent possible in the workstation. The
foilowing devices are described in their ReqUirements Specification:

CRT Display - Large Format Display
Rigid Disk - either Shugart's SA100X or SA400X
Floppy Disk - either Shugart's SA800 or SA850
Xerox Wire Tranceiver
Character Printer - Diablo's Beach printer
Engineering Response to the Star LSI Workstation Goals - May 1979 5




~,_______________________T_h_e__D_a_n_d_e_Ii_O_n_s_y_s_t_~_m________________________-'~
Central Processor Memory System


Processor Xerox Wire
I Additional Memory

(2901 and controller Memory Memory
based) (64K by 16) (64K by 16)
Rigid Disk
and controller
Mesa
Emulator LSEP controller


I

Display
Controller

Floppy Disk
Processor
(8085 _ Keyboard
based) Pointer Monitor
Bell

RS