IBM 3790 Communications System

Figure 1. Minimum and Maximum 3790 Control Storage Requirements

#9431 Min.

Control Storage Increment, Type

1-#1 602, 8K bytes

#1603, 16K bytes

Control Storage Increment, Type

11-#1 612, 8K bytes

#1613, 16K bytes

Total bytes 0

t> These ratings are generally lower than those normally achieved by IBM computer hardware. One user wrote the comment "not operator oriented" below the ratings which this individual provided. Four of the five users regarded

"cost" as an advantage of the 3790 system.D

The basic 3791 ControUer will permit up to a maximum of thirty-one 3271's and/or 3284/3286/328Irs in any combina-tion; additionaUy, up to four 3793 Keyboard-Printers can be accommodated via separate attachments. An 80- or 132-column line printer with a speed of up to 1551pm or a 410 Ipm 132-column printer can also be attached to the basic system.

The 3791 Controller can be expanded to accommodate up to three additional clusters of up to four 3793 Keyboard-Printers and two remote mM 2741 Communications Terminals each via 1 to 3 3792 Auxiliary Control Units. The expanded 3790 system can accommodate a second printer. The use of device attachments is defined as follows:

Control storage is available in 8K- or 16K-byte increments up to a maximum of 213K bytes. The requirements for control storage capacity are configuration- and usage-dependent. The procedure for determining the required storage for a given configuration is quite complex and is based on the quantities and types of attached devices, the number of devices operat-ing toncurrently, and communications line usage. See Figure 1.

The 3792 Auxiliary Control Unit allows additional 3793 Keyboard-Printers to be attached to the basic 3791 Controller and provides a communications capability for the attachment of remote IBM 2741 Communications Terminals.

Each 3792 Auxiliary Control Unit can accommodate up to four 3793 Keyboard-Printers and up to two communications lines for the one or two remote 2741 terminals as a subcluster to the 3791 Controller. However, if any 3792 Auxiliary Control Unit includes a line printer, its combined total of 3793's and remote 2741's cannot exceed four. Each attached

~793 Keyboard-Printer requires a separate 3793 Attachment.

Each attached communications line requires a separate Asynchronous Communication Control (a maximum of two per 3792) and the EIA Interface or IBM Leased Line Adapter.

The Adapter Base (one per 3792) is prerequisite to the Asynchronous Communication Control.

The 3791 Controller can accommodate up to three 3792 Auxiliary Control Units via the 3792 Attachment, and each 3792 can be located up to 2000 cable-feet from the 3791 Controller.

One 3792 Auxiliary Control Unit can be equipped with an 80-or 132-column line printer.

The 3411 Magnetic Tape unit and control Model 1 can be attached to the 3791 to provide magnetic tape output or input.

Model 3410 magnetic tape drive can be attached via the 3411.

A total of four drives per system is permitted.

Max.

1 3

82K

Configuration Support

#9165 #9169

Min. Max. Min. Max.

3 3 6 7

1 5

65K 65K 115K 213K

The Security Keylock feature, which permits power to be applied only when the key is in place, is available for the 3791 Controller and for each attached 3792 Auxiliary Control Unit.

CONFIGURATION SUPPORT #9431:

This

support level provides for the attachment of3277 Display stations Models 1 and 2, 3284/3286/3287 printers and the Model 3288 line printer. The 3791 Controller will permit up to a maximum of 31 of the devices enumerated above to be attached in any combination. In addition, up to four 3793 keyboard/printers can be attached. Up to three 3792 Auxiliary Control units can be attached. This Configuration support provides up to 16 concurrent operations per system.

CONFIGURATION SUPPORT #9165: This support offers all of .the capabilities of Configuration Support #9431 plus RJE function, full screen processing, 3270 compatibility, transmission speeds of up to 9600 bps, and up to 31 concurrent tasks including system printer tasks. It also provides ASCII support, and expanded 3790 DB/DC VTAM and TCAM host support.

CONFIGURATION SUPPORT #9169: This support pro-vides all of the functions of Configuration Support #9431 and

#9165. It also supports attachment of the 3276 Control Unit Display Station, 3278 Display and 3287 and 3289 printers via the Data Link Adapter, plus attachment ofthe 3411 Magnetic Tape unit and control Modell.

TRANSMISSION SPECIFICATIONS

Transmission between the 3790 Communication System and its host System/370 Computer is supported by Synchronous Data Link Control (SDLC). Transmission is half-duplex at 1200, up to 2400, or up to 9600 bits per second, as determined by one of three SDLC Communications Adapters that can be specified for the 3791 Controller. Transmission at 1200 bps is clocked via the SDLC Adapter; an EIA Standard R5-232 interface for use with an external modem or an integral IBM modem can be specified. Transmission at up to 2400 or 9600 bps is unclocked; an EIA Standard R5-232 interface is provided for an external modem, which must provide its own clocking.

The 3791 is transmission-compatible with the IBM 3704 and 3705 Communications Controllers operating under the Net-work Control Program (NCP) and can be used in a switched or non-switched point-to-point or a non-switched multipoint communications arrangement.

DEVICE CONTROL

Built around a minicomputer as its nucleus, the 3790 Communication System is designed to serve in a .stand-alone capacity as a shared-processor data entry system, gathering and editing data from as many as 52 local and remote operator stations and storing the data on diskettes or magnetic tape for later batch transmission (batch session) to

JI

REPRODUCTION PROHIBITED MAY 1979

C21-491-203 Programmable Tanninals

. . the host computer. When equipped with the Data Link Adapters, up to 80 additional remote devices can be con-trolled. As an alternative, the data can be transmitted to the host computer as it is edited (inquiry session), without being stored on diskettes. Magnetic tape can also provide input to the system.

All operations are executed under program control. The 3790 receives its operating software from the host computer via the communications facility. Following receipt of the software, the 3790 operates independently of the host system.

All 3790 programs are compiled and can be tested on the host System/370 computer prior to use on the remote 3790. The application programs are prepared by the user via a System/370 assembler and statements dermed in an IBM-supplied macro library. Program debugging is performed with the aid of a utility package, Program Validation Service (PVS), on the host computer. PVS also formats 3790 programs for storage at the host computer and later trans-mission to the 3790. Subsystem Support Services (SSS), another utility, controls 3790 program libraries at the host site and controls the transmission of 3790 programs from the host computer to the 3790.

COMPONENTS

3793 KEYBOARD-PRINTER: The 3793 is a modified Selectric II typewriter terminal oriented toward the functions of the 3790 system. It contains a serial impact printer that prints full characters at speeds up to 15.5 characters per second; input symbols total 88. Vertical forms movement and print positioning can be performed under program control.

The printer accommodates friction-fed or pin-fed (optional) continuous forms up to 15.5 inches wide; the printing width is 13 inches. Horizontal spacing is 10 to 12 characters per inch;

vertical spacing is 6 lines per inch.

The typewriter-style EBCDIC keyboard includes operator guidance lights and switches.

3277 DISPLAY STATION: The 3277 is a CRT display unit with a 14-inch (diagonal measurement) CRT screen. The display screen arrangement is dependent on the model, as shown below.

3277 Display: Mod~ 1 Model 2

Characters/ display: 480 1920

Lines/display: 12 24

Characters/line: 40 80

A character set of 64 ASCII characters, including upper case alphabetics, numerics, and special symbols is displayed in green against a dark background. Each character is formed by a 7-by-9 dot matrix.

3791 Controllers--ModellC Model2A Model2B Features

#1515 Local Channel Attachment

#3701 EIA Interface

1200 bps Integrated Modem:

#5500 Non-switched

#5501 Switched

"Includes maintenance.

Many keyboards are available for the 3277 Display Station, but only the 66-or 78-key EBCDIC typewriter-style keyboard can be used when the 3277 is employed as an operator station attached to the 3791 Controller. The 78-key version of the typewriter-style keyboard includes 12 Program Function keys, which are defined by the application program.

Not all features for the 3277 display stations are supported when attached to a 3791 controller. The following features are supported: Audible Alarm, Operator Identity Card Reader, Keyboard Numeric Lock, and Security Keylock.

See Report C25-491-101 for complete details on the 3270 components, including 3277 display stations and 3284, 3286, and 3288 printers.

PRINTED OUTPUT: Printed copy is produced at a rated speed of up to 1551pm with a 48-character print belt, 120 lpm with a 64 character set, and 80 Ipm with a % character set by the #4710 and #4711 line printers for the 3791 or #4712 and

#4713 for the 3792. These printers have 80 or 132 print positions and accommodate 6-part, continuous pin-fed forms up to 8 inches (80 columns) or 14Ys inches (132 columns) in width. Horizontal and vertical spacings are 10 characters per inch and 6 lines per inch, respectively. The #4715 printer available with the 3791 operates at 410 Ipm with a 48 character set, 300 Ipm with a 64 character set, and 230 Ipm with a 96 character set. This printer provides 132 positions. Other characteristics are similar to the printers above except that program selection between 6 and 8 lines per inch vertical spacing is included for Configuration Support #9165 and

#9169.

MAGNETIC TAPE INPUT/OUTPUT: The IBM 3411 Magnetic Tape Unit and Control model 1 can provide input and output to a 3791 Control Unit. Additional magnetic tape capacity is provided by attaching 3410 Magnetic Tape units via the 3411. A total offour magnetic tape units per system are supported.

DATA LINK ADAPTER: The Data Link Adapter permits attaching the 3276 Control Display Stations plus 3278 Display Stations and 3287 or 3289 printers to a 3791 via non-switched communications lines. Only SDLC communica-tions protocol and the 1920 character screen format are supported. A maximum of five Data Link Adapter features can be attached to a 3791 controller. The maximum number of 3276 Control Display stations permitted on each Data Link Adapter is also five. A maximum of 80 units in any combination are permitted on the five Data Link adapters.

PRICING

All 3790 components, except the 2741 terminal, are available under the terms of IBM's Rental or Lease A[!I'eement (LRA) or for purchase. LRA includes prime-shift maintenance; a separate contract is available for purchased units.

Monthly Rental*

Short Ext. Monthly

Tenn Tenn Purchase Maint.

$541 $460 $lB,700 $204.00

717 610 24,800 194.00

893 760 30,900 248.00

88 75 3,000 4.00

12 10 400 4.00

19 16 630 5.00

25 21 860 7.00

C21·491·204

Programmable Terminals

IBM 3790 Communications System

Monthly Rental*

Short Ext.

Term Term Purchase

SOLe Feature:

#6301 With Business Machine Clock (for 1200 bps) 19 16

#6302 Without Business Machine Clock (for up to 2400 bps) 12 10

#6303 Without BUSiness Machine Clock (for up to 9600 bps) 35 30

#6350 Security Keylock 35** 35**

Control Storage:

#1590 Control Storage Expansion 31 26

Control Storage Increments:

#1602 Type I. 8K bytes 32 27

#1603 Type IA. 16K bytes 58 49

#1612 Type II. 8K bytes 32 27

#1613 Type IIA. 16K bytes 58 49

Additional Disk Heads for 3791 1 B. 1 C. 2A. or 28 32 27 Attachment

Features-#7911 3270 Attachment. First 38 32

#7912 3270 Anachment, Additional 32 27

#7900 3792 Attachment 36 31

#7901 3793 Anachment. First 36 31

#7902 3793 Anachment, Second 36 31

#7903 3793 Attachment, Additional 36 31

#7840 Magnetic Tape Anachment 182 155

Line Printers for 3791 :

#4710 155 Ipm, 80 print positions 177 161

#4711 1 66 Ipm. 1 32 pri nt positions 199 169

#4715 410 Ipm. 132 print positions 351 299

3792 Auxiliary Control Unit 200 170

#4712 Line Printer. 155 Ipm. 80 print positions 274 233

#4713 Line Printer. 155 Ipm. 132 print pOSitions 306 260

#7901 3793 Anachment 36 31

#1622 Control Storage Increment. 8K bytes 32 27

Communications

Features-#1021 Adapter Base 49 42

#1081 Asynchronous Communications Control 19 16

#3701 EIA Interface 12 10

#5400 Leased Line Adapter 19 16

#6350 Security Keylock 35** 35**

#4450 Forms Stand 54** 54*'

3793 Keyboard Printer 119 101

#5560 Power Line Keylock 75'* 75'*

3411 Modell Magnetic Tape Unit and Control (requires #7003 and 454 381

#3211 or #3221)

3410 Modell Magnetic 'Tape Unit (re(juires #3211 or #3221) 206 173

#7003 3790 Attachment 83 70

#3211 Single density; 1600 bpi PE 60 50

#3211 Dual Density; 800/1600 bpi 88 74

'Includes maintenance

"Single use chargell

670 450 1.200 35

1.055 637 1.170 637 1.170 1.080

1.300 1.100 1,300 1.300 1.300 1.300 6.200

6.176 6.826 11.960 6,900 9.600 10.500 1.300 637 1.700 650 400 650 35 54 3.450 76 12.460 5,655 2.315 1,835 2,646

Monthly Maint.

3.00 2.50 10.50

5.50 5.00 10.00 5.00 10.00 17.00

5.00 3.00 4.00 3.00 5.50 3.00 8.00

66.00 59.60 114.00 34.50 56.00 59.50 3.00 6.00 1.00 3.00 4.00 6.00

28.00

95.00 61.50 3.50 9.50 36.60

MAY 1979

C21-491-203 Programmable Tenninals

Im Dokument IBM 3770 Family Batch Communications Terminals (Seite 66-69)