IBM 3174 Introduction

• Serial Original Equipment Manufacture Interface (SOEMI)
•
16/4Mbps Token-Ring Network Gateway feature
• Concurrent Communication Adapter (CCA)
• Single Link Multi-Host Support option.
Local Customization
Terminals
Displays
All 3174 controller models have either a 1.2MB or 2.4MB high-capacity diskette
drive. Microcode diskettes
are shipped with each controller. These diskettes are
used to generate an
IML disk (either a diskette or a fixed disk) which supports the
configuration of
display stations and printers on your system. The IML disk gives
the 3174 all of the
information about the system that is necessary when power is
turned on.
To customize a disk, the operator follows a documented procedure for
typing in the system configuration features at the keyboard of a control unit
terminal (attached to the controller).
A
disk that has been customized by a user can be recustomized to remove features
or meet the changing needs of his system. Backup IML diskettes can be generated
with a
similar procedure.
The 3174
controller provides for the 3270 system's attachment to a data processing
system and the operation of attached terminals. The attached
terminals may be
either of two kinds: distributed function terminals (DFTs) or control unit terminals
(CUTs).
Distributed function
terminals (DFTs) interpret the data stream and execute
functions independently of the 3174 controller. The 3174 passes outbound
information from the host to the terminal; upon the
terminal's request, the 3174
then
transmits data prepared by the terminal inbound to the host.
Control
unit terminals (CUTs) cannot interpret the data stream themselves, nor can
they execute functions independently of the
controller. The 3174 interprets the data
stream and executes functions
for the control unit terminal.
Many models of display stations are supported by the 3174 controller (see the
"Table of 3174 Controller Devices" on page A-1). The display models differ in:
• Screen size
• Character size
• Spaci ng between lines of type
• Character color
• Background color.
Displays also have many common characteristics. All
models follow the same
architecture and share a common data stream format. Other shared
characteristics include:
• Ability to adjust screen brightness
• Etched or filter-bonded screen surfaces
• Clear, stable screen imaging.
Chapter 2. Features and Functions of the 3174 Controller 2-19

IBM 3174 Specifications

General

Brand	IBM
Model	3174
Category	Controller
Language	English