burroughs 205 User manual

HANDBOOK
OF
Bulletin 3034-A
Revised June, ~ 960
OPERATING PROCEDURES
FOR THE
BURROUGHS
ELECTRONIC DATA-PROCESSING SYSTEMS
Burroughs Corporation
DETR 0 IT, MICHIGAN

Section
1
1-1
1-3
1-5
1-8
1-11
1-14
1-18
1-21
1-24
2
2-1
2-3
2-6
2-9
2-19
2-21
2-26
2-32
2-42
2-43
2-45
2-47
2-52
2-53
2-60
3
3-1
3-4
3-5
3-7
3-9
3-11
3-13
3-18
3-21
3-26
3-31
3-33
3-38
3-39
3-42
3-47
4
4-1
4-3
4-4
4-8
TABLE OF CONTENTS
Title
INTRODUCTION
General .................................................................. .
Description ............................................................... .
The Computer .......................................................... .
The Control Console ..................................................... .
Supervisory Printer ..................................................... .
Paper-Tape System ...................................................... .
Punched-Card System .................................................... .
Magnetic-Tape System ................................................... .
Scol?e of Handbook ........................................................ .
THE COMPUTER
General .................................................................. .
Supervisory Control Panel .................................................. .
DC On-Off Indicator and Buttons .......................................... .
Register Displays .. · ...................................................... .
Clear Push Button ....................................................... .
Timing Toggle .......................................................... .
Operation Controls ...................................................... .
Computer-Stop Indicators and Controls ..................................... .
Sub-Maintenance Control Panel .............................................. .
General ................................................................ .
D-to-C Push Button ...................................................... .
Ignore-Sign-Column Switch ............................................... .
Operating Procedures ...................................................... .
Manual Operation ....................................................... .
Continuous Operation .................................................... .
CONTROL .CONSOLE ..................................................... .
General .................................................................. .
Control Panel ............................................................ .
General ................................................................ .
Register Displays ........................................................ .
Clear Push Button ....................................................... .
Timing-Toggle Indicators ................................................. .
Operation Controls and Indicators .......................................... .
Breakpoint Controls ..................................................... .
Input Selector .......................................................... .
Output Selector ......................................................... .
P. 0. Suppress .......................................................... .
Computer-Stop Indicators and Control ...................................... .
Decimal Keyboard ......................................................... .
Characteristics .......................................................... .
Operation .................. · ............................................ .
Consolette ................................................................ .
PHOTOELECTRIC READER AND HIGH-SPEED PAPER-TAPE PUNCH ........ .
General .................................................................. .
Photoelectric Reader ....................................................... .
Characteristics .......................................................... .
Mounting the Loop Adapter ............................................... .
Page
1-1
1-1
1-1
1-1
1-1
1-1
1-1
1-2
1-2
1-2
2-1
2-1
2-1
2-1
2-1
2-4
2-4
2-4
2-4
2-6
2-6
2-6
2-6
2-6
2-6
2-7
3-1
3-1
3-1
3-1
3-1
3-1
3-1
3-1
3-1
3-2
3-2
3-3
3-3
3-3
3-3
3-4
3-4
4-1
4-1
4-1
4-1
4-1

Section
ii
4-12
4-16
4-18
4-20
4-21
4-23
5
5-1
5-2
5-5
5-15
5-17
5-18
5-21
5-32
5-37
5-38
5-40
5-42
6
6-1
6-3
6-4
6·16
6-21
6-24
6-27
6-29
6-30
6-34
6-39
6-41
6-42
6-44
6-49
6-52
6-53
6-55
6-57
7
7-1
7-2
7-6
7-10
7-14
7-15
7-26
7-35
7-47
TABLE OF CONTENTS (Cont)
Title Page
Mounting the Reel Adapter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
Reading Paper Tape . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
Rewinding Paper Tape . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
High-Speed Paper-Tape Punch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
Loading Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
SUPERVISORY PRINTER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
Flexowriter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
Keyboard and Controls, Standard Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
Keyboard and Controls, CARDATRON-Code Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
Typewriter Control Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2
Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2
Control Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
Patch Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-5
Operating Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
Format Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
Tape Preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
Tape Duplication and Listing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
THE PAPER-TAPE PREPARATION SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
Controls and Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
Control Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
Keyboard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
Tape Punch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2
Tape Reader . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2
Tape Punching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2
Tape Verification and Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3
Verification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3
Error Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3
Verification of Special Tapes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4
Tape Duplication and Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4
Duplication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4
Error Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
Duplication of Special Tapes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Miscellaneous Operating Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Marking Tape . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Power Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Resetting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
THE CARDATRON SYSTEM................................................ 7-1
Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 -1
CARDATRON System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Card-Handling Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Designation of CARDATRON Input-Output Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Controls and Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Control-Unit Control Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Output-Unit Control Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-2
Input-Unit Control Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-4
Operating Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-6

Section
7-48
7-50
7-52
7-58
7-60
8
8-1
8-2
8-4
8-9
8-10
8-12
9
9-1
9-5
9-6
9-10
9-15
9-20
9-25
9-31
9-38
9-46
9-47
9-58
9-60
9-61
9-62
9-64
9-66
9-68
9-83
9-85
9-87
9-89
10
10-1
10-5
10-6
10-11
10-14
10-15
10-19
11
11-1
11-3
11-6
11-7
TABLE OF CONTENTS <Cont)
Title
Preparation of Card-Handling Units ........................................ .
Clearing the CARDATRON ............................................... .
Starting the Card-Handling Machines ....................................... .
Run-Out Procedure for the 089 Collator ..................................... .
Clearing Card Jams ..................................................... .
THE PUNCHED-CARD CONVERTER ....................................... .
Characteristics ............................................................ .
General ................................................................ .
Control Switches ........................................................ .
Operating Procedures ...................................................... .
Pre-Start ............................................................... .
Start ........................................ · · ·. · · · · · · · · · · · · · · · · · · · · · · ·
THE MAGNETIC-TAPE SYSTEM .......................................... .
General .................................................................. .
Magnetic-Tape Control Unit ................................................. .
Physical Description ..................................................... .
Read Subpanel ........................................................... .
Designate Subpanel ...................................................... .
T Register ............................................................. .
Control Subpanel ........................................................ .
Write Subpanel ......................................................... .
Operating Controls ...................................................... .
Tape Storage Unit ......................................................... .
Control Panel ........................................................... .
Unloading Procedures .................................................... .
Loading Procedures ........................................... , ......... .
DATAFILE .............................................................. .
Designated Indicator ..................................................... .
Not-Ready Indicator ..................................................... .
Not-Write Indicator ...................................................... .
Control Panel .......................................................... .
File-Protect Tabs ........................................................ .
Designate Switch ........................................................ .
Drive-Roller Retracting Handles ........................................... .
Preparing for Remote Operation ........................................... .
MAGNETIC-TAPE CALIBRATION .......................................... .
General .................................................................. .
Tape Storage Unit ......................................................... .
Even Lane ............................................................. .
Odd Lane .............................................................. .
DATAFILE .............................................................. .
All Odd Lanes .......................................................... .
All Even Lanes .......................................................... .
OPERATING SUGGESTIONS .............................................. .
General .................................................................. .
Before and After Operation ................................................. .
The Computer ............................................................ .
Checking Manually Stored Words .......................................... .
Page
7-6
7-6
7-6
7-8
7-8
8-1
8-1
8-1
8-1
8-1
8-1
8-1
9-1
9-1
9-1
9-1
9-1
9-1
9-2
9-2
9-3
9-4
9-4
9-4
9-5
9.7
9.9
9.9
9-9
9.9
9-9
9-12
9-12
9-12
9-12
10-1
10-1
10-1
10-1
10-2
10-2
10-2
10-3
11-1
11-1
11-1
11-1
11-1
iii

Section
11-9
11-11
11-13
11-15
11-19
11-20
11-23
11-31
11-32
11-34
11-36
11-37
11-39
11-41
11-43
TABLE OF CONTENTS (Cont)
Title Page
Storage Drum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-1
Power Failure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-2
Air-Conditioning Fail-are . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-2
Cycling Down the Computer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-2
The Magnetic-Tape System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-2
DATAFILE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-2
Tape Storage Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-3
Paper-Tape System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-4
Manually Rewinding Paper Tape . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-4
Splicing Paper Tape . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-4
Sample Forms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-4
Computer Log . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-4
Control Console Stop Sheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-4
Pre-Run Check Sheets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-4
Console Notebook . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-4
TABLES
Table Title Page
2-1 Effects of Various Settings of the Lock-Normal and Continuous-Step Switches. . . . . . . . . 2-5
5-1 Patch-Panel Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
7-1 CARDATRON System Row-Counter Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-5
Figure
2-1
2-2
2-3
2-4
iv
3-1
3-2
3-3
3-4
4-1
4-2
4-3
4-4
4-5
5-1
5-2
5-3
5-4
5-5
5-6
6-1
6-2
FIGURES
Title
Burroughs 205 Computer ................................................... .
Supervisory Control Panel .................................................. .
Neon Indicators and Set Buttons ............................................. .
Sub-Maintenance Control Panel .............................................. .
Control Console ........................................................... .
Control-Console Control Panel ............................................... .
Decimal Keyboard ........................................................ .
The Consolette ............................................................ .
Photoelectric Reader ....................................................... .
Loop Adapter ............................................................. .
Reel Adapter ............................................................. .
Position of Paper Tape in Photoelectric Reader ................................. .
High-Speed Paper-Tape Punch ............................................... .
Flexowriter and Typewriter Control Unit ...................................... .
Flexowriter Keyboard, Standard Model ....................................... .
Flexowriter Keyboard, CARDATRON-Code Model .............................. .
Typewriter Control Unit Panel .............................................. .
Patch Panel .............................................................. .
Mechanical Reader and Punch ............................................... .
Tape-Preparation System ................................................... .
Control Unit .............................................................. .
Page
2-2
2-3
2-4
2-6
3-2
3-3
3-3
3-4
4-2
4-3
4-3
4-4
4-4
5-2
5-3
5-4
5-5
5-5
5-7
6-2
6-2

TABLE OF CONTENTS (Cont)
figure Title Page
6-3 Tape-Preparation System Keyboard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3
6-4 Tape Punch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4
6-5 Tape Reader . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
6-6 Verified Tape . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
7-1
7-2
7-3
7-4
7-5
7-6
8-1
9-1
9-2
9-3
9-4
9-5
9-6
9-7
9-8
11-1
11-2
11-3
11-4
CARDATRON System ...................................................... .
CARDATRON Unit Designation ............................................. .
CARDATRON Control Unit Control Panel .................................... .
CARDATRON Output Unit Control Panel ..................................... .
CARDATRON Input Unit Control Panel ...................................... .
089 Control Panel ......................................................... .
Punched-Card Converter Control Panel ........................................ .
Reel-Type Tape Storage Units ............................................... .
DATAFILE's ............................................................. .
Tape Control Unit Control Panel ............................................. .
Tape Storage Unit Control Panel ............................................. .
Indicators Above Control Panel .............................................. .
DATAFILE Control Panel .................................................. .
File-Protect Tabs .......................................................... .
Vacuum Manifold and Drive-Roller Assembly .................................. .
Sample Computer Log ..................................................... .
Console Stop Sheet ........................................................ .
Control Console and Supervisory Control Panel Set-Up Sheet ..................... .
Peripheral-Equipment Set-Up Sheet .......................................... .
7-2
7-3
7-4
7-4
7-7
7-7
8-2
9-2
9-3
9-4
9-5
9-10
9-10
9-11
9-12
11-5
11-6
11-7
11-8
v

TYPICAL BURROUGHS 205 COMPUTING SYSTEM INSTALLATIONS
BOSTON NAVAL SHIPYARD
MINNESOTA MUTUAL LIFE INSURANCE COMPANY, AT ST. PAUL, MINNESOTA
vi

INTRODUCTION
1-1 • GENERAL
1-2. The Burroughs 205 Electronic Data-Processing Sys-
tem is a medium-scale computing system. Burroughs 205
systems may consist of one of a number of different
configurations, since a variety of input-output equipment
is available and not every installation has all of this
equipment. It is not the purpose of this handbook to
discuss possible variations of the system configuration,
but, rather, to describe each of the units available. The
operator will, of course, select the information he needs
from that which is presented here.
1-3. DESCRIPTION
1-4. A maximum Burroughs 205 Electronic Data-Proces-
sing System includes the computer, the Control Console,
a supervisory printer, paper-tape and punched-card input
and output systems, and magnetic-tape auxiliary storage.
1-5. THE COMPUTER
1-6. The computer is the data-processing and control
center of the Burroughs 205 system. (Refer to section 2.)
It automatically executes internally stored, sequential pro-
grams of single-address instructions. Instructions and
data are stored in static registers and on a magnetic
drum. The computer accepts data and instructions from
punched paper tape, or-through the CARDATRON* sys-
tem or the Punched-Card Converter-from punched cards,
or from magnetic-tape auxiliary storage. It is also pos-
sible to insert data and instructions manually.
1- 7. The supervisory control panel on the computer con-
tains indicators which show the operator the contents
of the static registers, the mode in which the computer
is operating, and some of the reasons for computer stops.
The controls enable him to place the computer under
program control or to operate it manually when he
wishes to make insertions in storage, inspect data, com-
pare words, and so forth. The operator may also use a
few of the controls on the sub-maintenance control panel
on the computer, although most of these controls are
intended for the use of the field engineer (paragraphs
2-45 through 2-51).
1-8. THE CONTROL CONSOLE
1-9. The computer may also be operated from the Con-
trol Console, a separate desk-sized unit (section 3) . The
Control Console includes a control panel and a decimal
keyboard for manual entry of information into storage.
*TradP-mark of thP Burroughs Corporation
Many of the controls and indicators duplicate those on
the supervisory control panel. There is provision on the
Control Console, however, for breakpoint control, the
suppression of printout, and the selection of one of three
devices for providing input in response to a PAPER·
TAPE READ instruction, as well as selection of printout
or punchout in response to a PAPER-TAPE WRITE
instruction. None of these facilities is available at the
supervisory control panel.
1-10. The operations of the supervisory control panel and
the Control Console are closely interdependent, and the
operator is cautioned that he must be familiar with the
implications of this interdependence before attempting
to operate the system. Refer to sections 2 and 3.
1-11. SUPERVISORY PRINTER
1-12. The supervisory printer is used to print out small
quantities of data, such as interim results of program
runs and program-control information (program identi-
fication, date, and so forth) . It may also be used to
print out directions to the operator coincident with error
or program-control stops.
1-13. The supervisory printer used with the Burroughs
205 system is a Flexowriter modified to operate under
control of the Typewriter Control Unit (section 5). Under
program control, the supervisory printer can type or
punch-or simultaneously type and punch-numeric or
alphanumeric information from the computer. The Flexo-
writer is also used off-line to duplicate a paper tape
or to punch a new tape. The mechanical reader that is
part of the Flexowriter can be used as an input device to
the computer, but rarely is, in actual practice, since it
is relatively slow.
1-14. PAPER-TAPE SYSTEM
1-15. PHOTOELECTRIC READER AND HIGH-SPEED
PAPER-TAPE PUNCH. The Photoelectric Reader and
the High-Speed Paper-Tape Punch are the primary paper-
tape input and output devices used with the Burroughs
205 Data-Processing Systems (section 4). The Photo-
electric Reader reads information from paper tape under
the control of instructions from the computer. It is
selected as the paper-tape input device from the Control
Console.
1-16. The High-Speed Paper-Tape Punch operates through
the Control Console to reproduce information from the
computer in paper tape.
1-1

Introduction
1-17. PAPER-TAPE PREPARATION SYSTEM. The
Paper-Tape Preparation System is an off-line device used
to punch, verify, and duplicate paper tape for later use
as input to the computer through the Photoelectric
Reader. It consists of a control unit, a keyboard, a tape
punch, and a tape reader (section 6) .
1-18. PUNCHED-CARD SYSTEM
1-19. CARDATRON SYSTEM. Punched-card input and
output to the computer is from and to standard IBM
card-handling equipment through the CARDATRON sys-
tem, which consists of a CARDATRON Control Unit and
up to a total of seven CARDATRON input and output
units (section 7). Each of the input and output units is
connected to an IBM device. Input usually is from an
IBM card reader and output is to a card punch or line
printer. The CARDATRON input and output units pro-
vide buffering of information passing between the com-
puter and the card-handling devices. This buffering en-
ables simultaneous multiple-input-output operation.
1-20. PUNCHED-CARD CONVERTER. Card input to
the computer may also be through the Punched-Card
Converter. This is a relatively slow device, which pro-
vides no buffering and can handle only numeric in-
formation. However, it provides an economical means
of communication between card-handling machines and
the computer. The punched-card converter will handle as
many as 40 positions of alphabetic printed output, when
it is coupled with the Type 407 line printer and special
plugboard wiring is employed.
1-21. MAGNETIC-TAPE SYSTEM
1-22. Magnetic tape is used as auxiliary storage for the
Burroughs 205 Electronic Data-Processing Systems. In-
formation is written on or read from magnetic tape
under computer control. It may consist of data or in-
structions, or both.
1-23. Two types of magnetic-tape storage units may be
used with the computing system, a conventional reel-
type unit or the multiple-tape bin-type DATAFILE*.
The DATAFILE is a large-capacity storage device con-
taining 50 tapes and having a total capacity of 100,000
*Trade-mark of the Burroughs Corporation
1-2
20-word blocks, as opposed to the 20,000 20-word block
capacity of the reel-type units. Up to ten DATAFILE's
or reel-type storage units-or any combination totaling
ten-may be used with a single Burroughs 205 system.
Refer to section 9. One tape control unit is necessary to
control and operate each ten-unit group or any part
thereof.
1 -24. SCOPE OF HANDBOOK
1-25. This handbook is intended for the use of two types
of persons: first, the operator; and second, the pro-
grammer and coder, who must understand system opera-
tion in order to provide intelligent instructions to the
operator. Instructions are given for operating the units
of the system-procedures for starting and stopping, for
entering information into storage, for examining in-
formation in storage, and for loading and unloading
paper tape and magnetic tape, and so forth. No attempt
is made to describe the IBM equipment in detail, since
IBM manuals are available which contain this informa-
tion (paragraph 7-9).
1-26. The book was written on the assumption that the
logic and coding of the program have been checked
out as co"mpletely as possible by the coder before the
operating instructions for the program are given to the
operator and that the operator has been supplied with
stop listings (error stops, breakpoint stops, program stops,
and so forth), a pre-run check sheet, Control Console
and supervisory control panel set-up sheets, peripheral-
equipment set-up sheet, and other standard operating aids.
It is suggested that the operator compile a console note-
book to organize this material (paragraphs 11-44 through
11-54).
Please address queries or comments concerning this hand-
book to:
Manager, Product Support, 205
Burroughs Corporation
6071 2nd Ave.
Detroit 2, Michigan

2-1 • GENERAL
2-2. The Burroughs 205 is a general-purpose stored-
program electronic digital computer. It is the central
controlling and processing unit of the data-processing
system. The computer is designed to solve a wide variety
of data-reduction and data-handling problems. It stores
information on a magnetic drum and in static registers
(groups of bi-stable electronic devices commonly called
flip-flops or toggles). It automatically carries out sequen-
tial programs of single-address instructions.
2-3. SUPERVISORY CONTROL PANEL
2-4. The supervisory control panel is located in the top
third of the central section of the computer (figure 2-1) .
It is used by the operator, for program checking and for
operating the computer, and by the field engineer for
maintenance purposes. (The system may also be operated
from the Control Console. Refer to section 3.)
NOTE
When the supervisory control panel is to be used
for operating the system, the stop button on the
Control Console must first be depressed.
2-5. The supervisory control panel has five register dis-
plays and one control display, plus test-system, d-c, com-
puter-stop, clear, timing-toggle, operation, and memory-
control subpanels (figure 2-2). The operator is concerned
only with the following displays and subpanels:
Registers (paragraphs 2-9 through 2-18)
D-c (paragraphs 2-6 through 2-8)
Computer-stop (paragraphs 2-32 through 2-41)
Clear (paragraph 2-19)
Timing-toggle (paragraphs 2-21 through 2-25)
Operation (paragraphs 2-26 through 2-31)
He uses the zero push button on the test system subpanel
for one operation only (paragraph 2-13) . Otherwise, the
test-system, control, and memory-control subpanels are
solely for the use of the field engineer.
2-6. DC ON-OFF INDICATOR AND BUTTONS
2-7. Depressing the DC ON button causes direct current
to be supplied to the computer and the d-c indicator to
come on, provided that the field engineer has started the
computer from the Power Control Unit. Depressing the
OFF button causes de to be cut off.
CAUTION
In using any of the controls near the DC buttons
(figure 2-2) , be very careful not to press the
ER
red DC OFF button accidentally, since all infor-
mation in the quick-access bands will be lost,
and the program currently in operation must be
restarted from the first restart point which does
not require retention of data in the quick-access
bands.
2-8. If de should be cut off accidentally, wait 4 or 5 sec-
onds and then proceed as follows:
1. Turn off the CARDATRON core-voltage switches.
(These switches are located inside the input, output,
and units on the side panels.)
2. Press the DC ON pushbutton.
3. Press the clear buttons on the supervisory control
panel and the Tape Control Unit.
4. Turn on the CARDATRON core-voltage switches.
5. Restart the program from the first restart point
which does not require retention of data in the
quick-access bands.
2-9. REGISTER DISPLAYS
2-10. GENERAL. The static registers of the Burroughs
205 use flip-flops as the principal numerical and logical
elements. These electronic devices are always in one of
two stable states; the logic of the machine uses one state
to indicate zero and the second state to indicate one. The
two states are sometimes spoken of as off (zero) and on
(one), because when a flip-flop is in the zero state, the
corresponding neon on the control panel is off, and when
the flip-flop is in the one state, the corresponding neon is
on. Actually, the bi-stable devices themselves are never
off.
2-11. The registers are represented on the supervisory
control panel by banks of neon lamps. Each vertical col-
umn of neons represents the four bits of a decimal digit;
the value of this decimal digit is the sum of the values of
the lighted neons. Reading from top to bottom, the neons
repres~nt the values 8, 4, 2, and 1. No value greater than
9 should appear in any decade. For example:
Decades
8 0 • 0 0
4 • 0 0 0
2 • 0 0 0
1 • • 0 •
Legend: I on
0 off
7 9 0 1
Decimal-digit values
2-1

The Computer
SUPERVISORY CONTROL PANEL PANEL
COVERING SUB-MAINTENANCE
CONTROL PANEL
Figure 2-1. Burroughs 205 Computer.
If a value grea ter than 9 should appear , the FC (fo rbid-
den-combination) indicator will come on. Refer to para -
graph 2-34.
2-12. For each of the four neons in a column th ere is a
corresponding red set button in the same column, below
th e neons. A neon indicator in a column may be turned
on manually by depressing the corresponding set button.
(T he neon comes on, of course, because the flip-flop in
the re gister changes state when the button is depressed.)
For example, th e 4-bit neon may be turned on by depress-
ing the 4 set button (fig ure 2-3 ) .
2-13. A register may be cleared by depressin g the cl ea r
butt on for that register (fig ure 2-2) . A single neon may
be turn ed off by depressing the corresponding set button
and the z ero pushbutton on th e test-system subpane l at
the same time. All of the re gisters may be cleared by de-
pressing the red clear button next to the lock-normal
switch (p ara g raph 2-19) .
2-14. A REGISTER. This re gis ter contains 11 decimal-
digit positions. Ten positions are for the data or instruc-
tion, and one position is for the sign. This register acts as
an accumulator , and the results of most operations appear
here. Th e decimal-digit positions are marked A -S G, an·d
A-1 throu gh A-10.
2-15. R REGISTER. This register co ntains 10 decimal-
digit positions (no sign-digit position). In seve ral opera-
2-2
tions , it serves as an extension of the A register , holdin g
the least-sig nificant digits of a number con tained in the
combined A and R registers. The digit positions ar e
marked R-1 throu gh R-10. The sign of the R re gister is
th e sign of the A re gister.
2-16. D REGISTER. This register contains 11 decimal-
digit positions, marked D-SG, and D-1 throu gh D-10. All
words entering the C re gister or the A re gister, from an
input medium or from st orage, fir st pass throu gh the D
register. Although it is not used directly for program-
min g, the D register con tain s one of the operands durin g
an arithmetic operation. All skip, br e akpoint , unit-desig-
nation , and sign-control digits of an instruction are
sensed as the word passes from the D register to the C
register. Data e nterin g the B register also passes throu gh
th e D register.
2-17. C REGISTER. This register con tain s 10 decimal-
di git positions. The first two positions (high- order posi-
tions C-1 and C-2) contain the order or operation code,
and the next four (C-3 throu gh C-6) contain the address
of the operand, if there is an operand. The last four digit
positions (C-7 throu gh C-10) compr ise the co ntrol coun-
ter; these positions hold the storage address of the in-
struction to be executed following the instruction now in
the first six di g it positions of the C re gister (the order
re gist er and address register) . The C register receives
each instruction from storage throu gh the D register. Any
word e nterin g th e C re gister is treat ed as an instruction.

••
• oo :o 00§0
I
00 '• :• •••
@@ ® @: @@ ®@@@
@ @ @ @:@@ @@ (4) (t)
@@@ @:@ @ @@@@
G@@ @ :@ ®@@ (f)@
R R EGISTE R
, .., .-rt0t-o
t~ttot
0 0 0 G 0 0 ,.
t~A
('t•
.
0 0 0 0 0 0 0
<H
(g
0 0 0
Or
0
"'
0 0 0 0 0 0 0
'
@ @ @ @ @ @
@ @ @ @ @ (i)
@ @ @ @ @
@ @
(!) @ @ @
Figure 2-2. Supervisory Control Panel.
"" ...... <""""'- ((lW!.. +
OC.006000 , 00
oooeooQO
eoooo · oeo
OOOOOOOe>O
@ @ @ @ (9) @ (j} @ ~ (i)
~@@@@@@@i)•
@@@@~@Ci @@
@@@@@@@@@@
C REGISTER
....
=-
(1)
n
0
3
"tS
c:
...
C1)
..

The Computer
2-18. B REGISTER. This register contains four decimal-
digit positions marked B-1 through B-4. It is used for
tallying and automatic address modification of instruction
words. Under program control, the contents of the B reg-
ister can be added to the address part of any instruction
word, as the instruction passes from the D register to the
C ·register, thus leaving the word unchanged in storage.
0
- +-Indicator Turned On
Neon Indicators
0
0
@
@+set Button Depressed
Set Buttons
Figure 2-3. Neon Indicators and Set Suttons.
2-19. CLEAR PUSH BUTTON
2-20. The general-clear push button is the red button next
to the lock-normal switch (figure 2-2). When this button
is depressed, all registers and indicators will be cleared
(set to zero or off), except that the timing-toggle execute
indicator will be on. (The cleared state of the timing-
toggle is always execute.) Information in storage is not
affected. The clear push button may be used for emer-
gency stops. NOTE
Clearing the registers actually inserts the PA-
PER-TAPE READ instruction (00 0000 0000)
in the C register.
2-21. TIMING TOGGLE
2-22. INDICATORS. The timing-toggle indicators are
labeled FETCH and EXECUTE. They indicate the phase
of the timing cycle that the computer will enter next. If
the computer is in the fetch phase-fetching an instruc-
tion from storage-the execute indicator is on. If the
computer is in the execute phase-executing an instruc-
tion that has previously been fetched from storage-the
fetch indicator is on.
2-23. INDICATOR CONTROLS. The state of the timing
toggle may be changed manually from fetch to execute by
depressing the· push button under the indicator that is off.
2-4
2-24. LOCK-NORMAL SWITCH. During normal opera-
tion, this two-position switch is in the NORMAL position.
When this switch is in the LOCK position, the computer
will be locked in the execute phase; that is, it will be
prevented from changing from the execute to the fetch
phase of the timing cycle. If the computer is in the fetch
phase at the time the switch is set to LOCK, depressing
the clear button will lock the computer in the execute
phase. The execute indicator will remain on because the
only phase of the timing cycle that can be entered in the
lock state is execute.
2-25. Various modes of computer operation are based on
the combined settings of the lock-normal and continuous-
step switches. Refer to table 2-1.
2-26. OPERATION CONTROLS
~-27. ST ART. This button is used to start processing of
data. It can be used to initiate operation in either con-
tinuous or step mode. Note that if the computer is to be
operated from the supervisory control panel, the stop but-
ton on the Control Console must be depressed before the
start button on the supervisory control panel is pushed.
2-28. The phase of the timing cycle that the computer will
enter when the start button is pushed is indicated by the
timing-toggle indicator that is on (paragraph 2-22).
Either the next instruction will be fetched, or the contents
of the C register will be executed.
2-29. CONTINUOUS-STEP. With this switch in the con-
tinuous position, the computer will automatically execute
instructions in program sequence when the start button is
depressed.
2-30. The step setting has two functions. One function is
to enable step-by-step program debugging. With the
switch in the step position, one phase of the timing cycle
will be completed each time the start button is depressed.
The second function of the step setting is to enable opera-
tion from the Control Console. Always check to be sure
that the switch is set to step before attempting to operate
the computer from the Control Console.
2-31. The computer can be locked in the execute phase
with the continuous-step switch in either position by set-
ting the lock-normal switch (paragraph 2-24) to lock.
Refer to table 2-1.
2-32. COMPUTER-STOP INDICATORS AND
CONTROLS
2-33. IDLE INDICATOR. This indicator is on whenever
the computer is not operating in the continuous mode.
2-34. FC INDICATOR. This indicator comes on whenever
a forbidden combination (a binary-coded decimal digit
greater than 9) is detected in one of the registers. Since
digits enter the register from right to left, the forbidden
combination is detected in the lowest-order position
(A-10, R-10, B-4, D-10, C-6, or C-10). Refer to para-
graph 2-11.
2-35. The FC indicator is turned off by clearing the su-
pervisory control panel (paragraph 2-19) or by changing

The Computer
Table 2-1. Effects of Various Settings of the lock-Normal
and Continuous-Step Switches
Switch Settings Operations
Lock-Normal Continuous-Step
Lock Step
Computer locked in execute phase.
Each time the start button is depressed, the instruction in the C
register will be executed.
Lock Continuous
Computer locked in execute phase.
Can continuously execute instruction in C register after start but-
ton is depressed once.
Normal
Step Supervisory control panel setting for operation from the Control
Console.
Also, setting for step operation from the supervisory control panel
(providing the stop button on the Control Console has been
depressed).
Normal
Continuous
Can operate in continuous mode from the supervisory control panel.
Cannot step through a problem.
the bit combination that causes the stop to a permissible
combination. For example, the operator may change a
binary-coded 15 (all bits on) to a binary-coded 7 by turn-
ing off the 8 bit. If this procedure is followed, the com-
puter resumes continuous operation without any further
intervention; however, garbled information may have
been introduced into the processing. To avoid the latter
condition and also to determine the cause of the forbidden
combination, the operator should stop the computer by
manually depressing the stop button on the Control Con-
sole or by setting the continuous-step switch on the super-
visory control panel to the STEP position, prior to cor-
recting the forbidden combination. Not only does this
reduce the possibility of misinformation being processed
by the system, but it also permits detailed analysis of the
situation by the Field En·gineer, if necessary.
2-36. CONTROL INDICATOR. This indicator comes on
whenever a STOP (08) instruction is executed or when-
ever the computer stops on an overflow condition. (In the
latter case the overflow indicator also comes on.) The
control indicator is turned off after a STOP instruction,
and continuous operation is resumed, by depressing the
start button; it is turned off after an overflow stop by
depressing the reset push button under the control indi-
cator.
2-37. SECTOR INDICATOR. This indicator comes on
and the computer stops whenever the checking circuitry
detects a sector alarm. A sector-alarm stop indicates that
the computer's checking circuits have lost count of word
positions on the drum. The stop prevents information
from being read from or written into incorrect storage
locations. If the sector indicator comes on during a pro-
gram run, depress the reset button under the indicator
and restart the program. If the sector indicator comes on
again, call the field engineer.
2-38. OVERFLOW INDICATOR. This indicator is turned
on if any of the following conditions occurs:
1. Arithmetic overflow (a result exceeding the capacity
of the A register) during the execution of the vari-
ous addition and subtraction instructions, or dur-
ing division, extracting, or rounding.
2. Sign difference during the execution of an OVER-
FLOW ON SIGN DIFFERENCE (OSGD) instruc-
tion.
3. An attempt to execute a magnetic-tape instruction
while tape is in motion or while the designated tape
unit is not ready.
2-39. If any of the instructions that cause overflow is not
followed immediately by the CHANGE CONDITION-
ALLY (CC) instruction, the computer will stop with the
overflow, idle, and control indicators on. The fractional
sum or difference remains in the A register after an over-
flow on addition or subtraction. After an overflow on
division, however, the A and R registers are cleared.
2-40. The conditional change-of-control instructions
CHANGE ON NON-ZERO (CNZ), DECREASE B (DB),
and NORMALIZE (NOR) tlll\n on the overflow indicator
momentarily when the change of control is to be executed.
The computer does not stop, however.
2-41. AUDIBLE-ALARM TOGGLE SWITCH. When this
two-position switch is in the ON position, a buzzer will
sound whenever the computer stops, provided that the
audible-alarm switch on the Control Console is also set to
ON. The alarm can be turned off with either switch, or
when continuous operation is resumed.
2-5

The Computer
SICIOI c:ouM9
llC'ra.t
-.ouT CIDMMAHD
IGNOmt lllC"
Olm!Vt
~all.
'llST
e IUl'flll!SS
COMNMINT
llCIOll MAlllll 1llT
e._...._
"''"
·-
t..~~--l
-
..,.
'I '
..
lmlHAl
AUIOMA11C Ml
~~
"°'
~
.....,
.......
.....
...
--
Figure 2-4. Sub-Maintenance Control Panel.
2-42. SUB-MAINTENANCE CONTROL
PANEL
2-43. GENERAL
2-44. The sub-maintenance control panel (figure 2-4) is
located behind the panel directly beneath the supervisory
control panel. It is used by the field engineer for mainte-
nance purposes. However, there are two switches on the
pa.nel that are important to the operator: the D-to-C push
button and the ignore-sign-column dial switch.
2-4 5. D-TO-C PUSH BUTTON
2-46. During a fetch phase, all control digits in an
instruction are recognized in the D register, and the
controls are set from the D register. Under program
control, this function automatically takes place when the
instruction is fetched from storage and brought to the D
register. To enable' recognition of control digits when an
instruction is inserted manually, proceed as directed in
paragraph 2-55.
2-47. IGNORE-SIGN-COLUMN SWITCH
2-48. This three-position rotary switch is used on input
with the photoelectric and mechanical paper-tape readers,
and with the key board ( paragraphs 3-23 through 3-25 ).
It is not effective on either card or magnetic-tape input.
2-49. NORMAL. When the switch is in this position, all
sign arithmetic will be observed concerning input data;
that is, control words will be recognized as such and
pecified B-register address modification will occur.
2-50. IGNORE ALL. When the switch is in this position,
no sign arithmetic will be observed, that is, control words
\ ill not be recognized as such and no B-register address
modification will occur. All sign digits will be stored as
punched, or as entered from the keyboard.
2-51. IGNORE 2. With the switch in this position, opera-
tions performed when digits 2 and 3 appear in the sign-
digit position of any word during input are ignored.
Digits 2 and 3 remain in the sign-digit position of the
word when the word is sent to storage. (When reading
2-6
format bands into computer storage via paper tape, the
ignore-sign-column switch must be set to the IGNORE 2
position, if there are 2's in the sign positions of any
words of the format band.)
2-52. OPERATING PROCEDURES
2-53. MANUAL OPERATION
2-54. I NSERTIONS IN STORAGE. To s tor e data or m-
struction words:
1. Depress the stop button on the Control Console.
2. Set the lock-normal switch to LOCK (paragrap h
2-2 4) .
3. Set the continuous-step switch to STEP and press
the clear button. Pressing the clear button se ts the
timing toggle to the execute phase (paragrap h 2-19)
4. Insert in the A register the data or instruction word
to be stored by depressing the red set buttons to
form the binar y-coded decimal digits desired (para-
graph 2-12) .
5. Insert into the order register the STORE CLEAR
(02) instruction.
6. Insert into the address register the addr ess of the
storage location where the numb er in the A register
is to be stored.
7. Pre ss the start button. The STORE CLEAR (02)
instruction will be executed and the co mput er will
immediately stop.
8. To inspect the information now stored, change the
02 in the order register to 64 (CLEAR A DD) and
depress the start button.
2-55. INSERTIO N OF INSTRUCTIONS FOR IMME-
DIATE EXECUTION. Most instru ctions may be inserted
in the C register and executed by depressing the s tart
button. On certain occasions, however, the operator may
wish to enter manually and execute an instruction in
which the control digits are significant (paragrap h 2 -1 6).
Since these digits are sensed as they pass from the D to
the C register, an instruction in which they are significant

must be inserted in the D register. To do so, proceed as
follows:
1. Depress the stop button on the Control Console.
2. Set the lock-normal switch to LOCK.
3. Set the continuous-step switch to STEP.
4. The instruction to be executed is entered into the D
register by depressing the red set buttons on the
Supervisory Control Panel.
5. Depress the D-to-C push button on the sub-mainte-
nance control panel (paragraph 2-45). The ASYNC
neon on the control subpanel of the supervisory con-
trol panel will come on.
6. Return the lock-normal switch to NORMAL. The
instruction will be transferred Jo the C register, and
all control digits will be recognized.
7. Depress the start button. The instruction will be
executed.
2-56. TRANSFER OF CONTROL. To transfer control to
a stored instruction:
1. Press the stop button on the Control Console.
2. Press the clear button on the supervisory control
panel.
3. Set the continuous-step switch to whichever mode of
operation is desired, after the transfer.
4. Set the lock-normal switch to NORMAL.
5. Insert a transfer-of-control instruction in the order
register (for example, CU, CUB, etc). Insert in the
address register the location of the instruction to
which control is to be transforred.
6. Press the start button.
2-57. STEP-BY-STEP OPERATION. Assuming that an
instruction is in the C register, the timing toggle is set to
EXECUTE, and the control counter contains the address
of the next instruction to be executed:
1. Set the continuous-step switch to STEP and the lock-
normal switch to NORMAL.
2. Press the stop button on the Control Console.
3. Press the start button. The instruction in the C reg-
ister will be executed.
4. Press the start button again. The instruction in the
location specified by the control counter will be
fetched and inserted into the order and address
registers.
5. Press the start button again. The instruction in the
order and address registers will be executed.
The start button must be depressed once for each fetch
phase and once for each execute phase. As each execute
phase is completed, the progress of the problem may. be
observed in the A, R, B, C, and D registers.
2-58. INSPECTION OF DATA. Occasionally it is neces-
sary to inspect a series of data or instruction words stored
on the drum. To do this:
1. Press the clear button.
2. Set the continuous-step switch to STEP and depress
the stop button on the Control Console.
3. Set the lock-normal switch to LOCK.
The Computer
4. Insert a CLEAR ADD ( 64) instruction in the order
register.
5. Insert in the address register the address of the loca-
tion of the data to be displayed.
6. Press the start button.
7. Repeat steps 5 and 6 until all words in question have
been examined.
CAUTION
Make certain that the instruction inserted in the
C register is one that fetches, such as CLEAR
ADD, rather than one that stores, such as
STORE or STORE CLEAR. Otherwise, the con-
tents of the location specified will be destroyed.
2-59. WORD COMPARISON. To compare two words vis-
ually, that is, to bring a word into the D register without
destroying the contents of the A register:
1. Press the stop button on the Control Console.
2. Press the clear button on the supervisory control
panel.
3. Set the continuous-step switch to STEP.
4. Set the lock-normal switch to LOCK.
5. Insert 64 (CLEAR ADD) in the order register and
the address of the first word in the address register.
6. Press the start button. This puts the first word in
the A register.
7. Insert 71 (EXTERNAL CONTROL) in the order
register and the address of the second word in the
address register.
8. Press the start button. This puts the second word in
the D register.
This operation can be used either by operators who don't
have an external switch connected to the Punched-Card
Converter or by those who have an external switch but to
whom it is not important if the present setting is dis-
turbed. (The external switch is a black box used with the
Punched-Card Converter for automatically switching
between punched-card and printed-line output, for ex-
ample, switching between the 528 and the 407.)
2-60. CONTINUOUS OPERATION
2-61. To initiate or resume continuous operation, there
must be an instruction in the C register, and the control
counter must contain the address of the next instruction to
be executed, unless it is a transfer-of-control instruction,
such as a CU or CUB instruction.
1. Set the continuous-step switch to CONTINUOUS
and the lock-normal switch to NORMAL.
2. Press the start button.
To initiate continuous operation at the beginning of a
program, the C register is loaded manually, unless a
paper-tape read instruction is the first instruction in the
program. (Clearing the supervisory control panel auto·
matically inserts a paper-tape read instruction in the C
register.) At the beginning of a program, the timing tog-
gle must be set to execute.
2-7

CONTROL CONSOLE
3-1 • GENERAL
3-2. The Control Console (figure 3-1) is a desk-sized
operation center from which the operator can supervise
(and intervene in) the operation of the Burroughs 205
Data-Processing System.
3-3. The indicators and controls are grouped on a con-
trol panel mounted on a pedestal at the rear of the Con-
trol Console. A decimal keyboard is provided for manual
input of data (paragraphs 3-38 through 3-46) .
3-4. CONTROL PANEL
3-5. GENERAL
3-6. The register displays and many of the indicators of
the supervisory control panel are duplicated on the Con-
trol Console panel. In addition, there is provision for the
selection of paper-tape or manual keyboard input and
paper-tape or character-at-a-time printer output, the sup-
pression of printout, breakpoint control, and skipping the
execute phase of an instruction when desired (figure 3-2).
NOTE
When the system is operated from the Control
Console, the continuous-step switch on the su-
pervisory control panel must be set to STEP and
the lock-normal switch to NORMAL.
3-7. REGISTER DISPLAYS
3-8. The register displays are identical to those on the
supervisory control panel. Individual registers can be
cleared or bits changed only from the supervisory control
panel (paragraphs 2-10 through 2-18). Since manual en-
try to the registers on the Control Console is from the
keyboard, there are no set buttons under the displays.
3-9. CLEAR PUSH BUTTON
3-10. Depressing this push button clears the registers and
sets the timing toggle so that the next phase of the timing
cycle will be execute (paragraph 2-19).
3-11. TIMING-TOGGLE INDICATORS
3-12. The timing-toggle indicators function simultaneous-
ly with those on the supervisory control panel (para-
graph 2-22). They cannot be set from the Control
Console. During normal operation, the phases of the
timing cycle alternate so rapidly that the indicators do
not convey any useful information to the operator.
3-13. OPERATION CONTROLS AND INDICATORS
3-14. CONTINUOUS PUSH BUTTON AND INDICA-
TOR. When this button is depressed, the computer is
placed in the continuous mode of operation, automatically
fetching and executing instructions in program sequence.
The indicator is on whenever the computer is set to
run continuously or is actually in continuous operation.
3-15. NOT-READY INDICATOR. This indicator is on
whenever a switch on the supervisory control panel is
in a position that would prevent successful operation
from the Control Console (the continuous-step switch
set to CONTINUOUS, or the lock-normal switch to
LOCK, for example). It is also on when any of the
switches on the sub-maintenance panel is not in the
normal (up) position, or when the test-drum switch on
the supervisory control panel is set to TEST.
3-16. STOP. Depressing this push button causes a com-
puter stop after completion of the phase of the timing
cycle during which the button was pushed (fetch or
execute) . Information in the registers will not be lost.
Operation can be continued from the supervisory control
panel, or the computer can be operated in the step mode
from the Control Console. The continuous indicator goes
off and the idle and control indicators come on.
3-17. STEP. After the computer has been taken out of
continuous operation by depressing the stop button, de-
pressing the step button repeatedly will cause the com-
puter to first fetch and then execute one instruction of
the program at a time, thus enabling the operator to follow
the progress of the program by examining the contents
of the registers after each step. The button must be
pushed once for each fetch and once for each execute
phase of the timing cycle. The phase that the computer
will enter first (or next) is indicated by the timing-toggle
indicators (paragraph 2-22).
3-18. BREAKPOINT CONTROLS
3-19. BREAKPOINT SELECTOR. This four-position dial
switch is just below the B-register display. When it is
set to:
OFF, breakpoint codes in the program will be ignored.
4, breakpoint digit 4, 5, 6, or 7 will stop the computer.
2, breakpoint digit 2, 3, 6, or 7 will stop the computer.
l, breakpoint digit 1, 3, 5, 7, or 9 will stop the com-
puter.
3-1

Control Console
Figure 3-1. Control . Console.
The computer will always stop after executing the in-
struction that contains the breakpoint digit.
NOTE
A new operator is sometimes confused by the
fact that some instructions appear in the C
register on a breakpoint stop in a form other
than that in which they were originally written.
For systems which include magnetic tape, all
blocking instructions appear in the C register
with 20 added to the address. (Some systems
even add 200 to the address.) The CHANGE ON
NON-ZERO, NORMALIZE, and DECREASE B
instructions will appear in the C register with
an operation code of 28 on a breakpoint stop.
3-20. SKIP SWITCH. When the skip switch is in the
ON position, the computer will skip the execute phase
of any instruction with the digit 8 or 9 in the breakpoint
position of the instruction. When the skip switch is off,
the computer will ignore skip codes. If the skip code is
a 9 ( binary digits 8 and 1), the 9 can also be used as
a breakpoint code. (Refer to paragraph 3-19.)
3-2
3-21. INPUT SELECTOR
3-22. This is a three-position switch on the extreme right-
hand side of the control panel. The three positions are
MECH. READER , OPTICAL READER, and KEY-
BOARD.
3-23. MECH. READER. This position selects the paper-
tape reader attached to the Flexowriter as the means of
reading paper tape.
3-24. OPTICAL READER. This position selects the
Photoelectric Reader as the means of reading paper tape.
3-25. KEYBOARD. This position selects the decimal key-
board for manual input.
3-26. OUTPUT SELECTOR
3-27. This three-position dial switch is at the extreme
left of the control panel. The three positions· are TAPE ,
OFF , and PAGE.
3-28. TAPE. The High-Speed Paper-Tape Punch is select-
ed as the means of output.

Control Console
0 0 o:o0 • ii • .
"'
0 " 0 o :o o :• 0 '
0 0 0 0 Q Q . O 0
ARE<i15rER--~·····
e
Q,
0
0
0
0
• 0 G o :o 0 0 0 0.
0000 : 000000 ,
G G a.,. ;, ~ o G G 0. 0
.
-- R REGISTER .. ···-··-
. UI ,10 .;.
.
.. .
.~--·
0 ~ 0 0 0 o·o, 0 0 0 0 'O 0 6 !6 0 G 0 16 0 -
0 0 0
"°
0 • Of
0 0 0 •Q c;, • 10 0 •
<a 0 0 0 010 0 0 0
•0 0 i
t; ·
Cl 0 0
C ~tCI ,If:~
Figure 3-2. Control-Console Control Panel.
3-29. OFF. Neither of the two paper-tape output devices
is selected. If a paper-tape write instruction comes up
for execution while this switch is in the OFF position,
the computer will stop and the idle indicator will go on.
3-30. PAGE. The Flexowriter is selected to print or punch
output data or to do both simultaneously (table 5-1 ). If
the Flexowriter is not turned on, a print instruction will
cause the information to shift out of the A register, but
no print o ut will occur.
3-31. P. 0. SUPPRESS
3-32. When this switch is in the ON position, the com-
puter will ignore paper·tape system print-out instru ctions.
3-33. COMPUTER-STOP INDICATORS AND
CONTROL
3-34. IDLE , FC/SA , AND CONTROL. The IDLE,
FC/SA , and CONTROL indicators operate simultaneous-
ly with the IDLE , F. C. , SECTOR, and CONTROL indi-
cators on the supervisory control panel ( paragraphs 2-33
through 2-37 ), the only difference being that on the
Control Console a single indicator (FC/SA) comes on
for both forbidden-combination and sector alarms .
3-35. BREAKPOINT INDICATOR. The BKPT. indica-
tor comes on when the computer stops after executing
an instruction containing a breakpoint code.
3-36. OVERFLOW INDICATOR AND RESET BUT-
TON. The overflow indicator functions in the same man-
ner as the overflow indicator on the supervisory control
panel ( paragraphs 2-38 through 2- 4 0). If the reset button
is depressed, the indicator will go off and the overflow
toggle will be cle ar ed. To accomplish thi s, depress the
continuous button on th e Control Console.
3-37. AUDIBLE-ALARM SWITCH. The function of this
sw itch is th e same as the function of the audible-alarm
sw itch on the supervisory control panel. Both audible-
a larm switches must be set to ON for the switch on th e
Co nt rol Console to be e ff ecti ve . Th e ala rm can be turn ed
o ff with eith er sw itch or when continuous ope rati on is
resumed.
3-38. DECIMAL KEYBOARD
3-39. CHARACTERISTICS
3- 40. The keyboard is generally used to enter a few words
at a time-to insert corrections, add words to a pro g ram ,
or to insert or delete breakpoint codes in stored instru c-
tions ( paragraph 3-19) . Keyboard input automatically
goes to the D register.
3-4 1. Th e key board (fig ur e 3- 3) ha s 13 keys, one for
each of the decimal digits from ze ro throu gh nin e, t wo
blank keys, and one key, desig nat ed F, which is used to
generate a finish pulse. The finish pulse indicates the end
of a Burrou ghs 205 word. The F key is always de pr essed
to complete the ent ry of a wo rd int o the co mput er.
Figure 3-3. Decimal Keyboard.
3-3

Control Console
3-42. OPERATION
3-43. ENTERING INSTRUCTIONS. To insert an in-
struction into the C register:
1. Press the clear button on the Control Console to
put a PAPER-TAPE READ (PTR) instruction
(00 0000 0000) into the C register and to set the
computer in the execute phase.
2. Set the input-selector switch on the Control Console
to KEYBOARD.
3. Set computer operation to the step mode by press-
ing the stop button and setting the continuous-step
switch on the supervisory control panel to STEP.
4. Press the step button to initiate the execution of
the PTR instruction, to activate the keyboard and
to prepare the computer to receive (in the D regis-
ter) the information entered from the keyboard.
5. Enter, by depressing the appropriate keys, the 11-
digit instruction into the D register. {Each digit
entered appears first in the low-order digit position
and is shifted left one digit position as each suc-
ceeding digit is entered.)
6. If input is a single instruction or the final instruc-
tion of a series, enter a 6 followed by the control
digits, operation code, and the address part of the
instruction. This places the 6 in the sign-digit posi-
tion of the D register.
7. If input is a series of instructions for individual
execution {for example, a series of CLEAR ADD
instructions entered to permit examination of the
contents of various storage locations) , enter a 4
in the sign-digit position of each instruction. The
sign-digit 4 will keep the keyboard activated to
accept the subsequent instructions.
8. After the 11 digits have been entered, examine the
D-register display to see if the entry has been made
correctly.
9. Depress the F key {end of word). The last six
digits of the instruction will be transferred to the
C register.
3-44. LOADING STORAGE LOCATIONS. To load one
storage location or consecutive storage locations from the
keyboard:
1. Press the clear button on the Control Console.
2. Set the input-selector switch to KEYBOARD.
3. Set computer operation to continuous by pressing
the continuous button. {Be sure the continuous-step
switch on the supervisory control panel is set to
STEP and the lock-normal switch to NORMAL.)
4. Enter in the D register through the keyboard the
input instruction (4 0000 00 xxxx), where xxxx
is the storage location into which the first word is
to be inserted. Press the F key to transfer the
instruction to the C register.
5. Enter the first word to be stored in the D register
through the keyboard, using the standard 0 or 1
3.4
(+ or -) in the sign-digit position.
6. Subsequent words are inserted into consecutive
stora ge localions by repeating steps 5 and 6.
7. On completion of all entries into stora ge, destroy
the 4 0000 00 xxxx instru ction by pres sing the clear
button.
3-45. INSERTING BREAKPOINT DIGITS. To insert a
breakpoint digit in a program instruction, from the key-
board, follow the procedure described above for inserting
a single word into storage.
3-46. STARTING AT A GIVEN LOCATION. To start
the computer at the beginning of, or at a point within,
a program already loaded on the drum:
1. Following the procedure for inserting a single in-
struction in the C register {paragraph 3-43), insert
20 (CHANGE UNCONDITIONALLY) into the or-
der register and xxxx into the address register, where
xxxx is the address of the storage location of the
first instruction to be executed.
2. Press the continuous button for automatic sequential
operation or the step button if step-at-a-time opera·
tion is desired.
3-47. CONSOLETTE
3-48. The Consolette is a desk-top control unit that can
be used instead of the Control Console, if the installa-
tion does not have a paper-tape system. The register
displays and those controls having to do with the paper-
tape system (input- and output-selector and printout-
suppress switches) have been eliminated from the Con·
solette. Like the Control Console, the Consolette has
skip, breakpoint , clear, audible-alarm, and overflow-reset
controls, and not-ready and idle indicators. It also has
BREAKPOINT SWITCH
IDLE INDICATOR NOT-READY
INDICATOR
SKIP SWITCH
AUDIBLE-ALARM SWITCH
Figure 3-4. The Consolette