Section 1. Operator Information; Introduction - IBM 3274 User Manual

Section 1. Operator Information
Introduction
The function of your 3274 Control Unit is to direct all
communication between your organization's host system and
its associated display stations and printers. The 3274 and the
attached display stations and printers form a cluster of devices
used to execute your organization's applications.
The 3274 is available in the following models:
• Models lA, 1B, 1D, 21A, 21B, 21D, 31A, 31D, 41A, and 41D
are attached directly to a host system and can control up
to 32 devices.
• Models 1C, 21C, 31C, and 41C are attached to a host system
through a communication facility and can control up to 32
devices. .
•
Models 51C and 61C are attached to a host system through
a communication facility, an 8100 Information System loop,
or a 4331 Processor loop. The Model 51C can control up to
12 devices; the Model 61C can control up to 16 devices.
Figure I-Ion page 1-2 shows a 3274 Model lA, 1B, 1D, 21A,
21B, 21D, 31A, 31D, 41A, or 41D. Models 1C, 21C, 31C, and 41C
are similar, but do not have the Power/Interface rotary switch
and the Local/Offline indicator installed on the operator panel.
(See Figure 1-7 on page 1-18 and Figure 1-8 on page 1-19.) A
3274 Model 51C or 61C is shown in Figure 1-2 on page 1-2.
After the 3274 is set up or installed and customized (configured
for your installation), you will normally only have to turn on
the 3274 (with the correct 3274 system or load diskette loaded
into the diskette reader) to prepare it for operation. Depending
upon your organization's applications, however, you may be
required to load different diskettes for different system
applications.
Section
1.
Operator Information
1-1