EM3270 Manual

Dual-Application Session
1-6 110332—Tandem EM3270 Manual
Product Components and Operation
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User control: A user can configure and start the EM3270 emulator from any
Tandem, IBM, or Fujitsu terminal that has an active command interpreter. The user
performs the functions otherwise performed by a central operator, in addition to the
user functions of the application.
In either case, the terminal emulates the IBM 3270 information display system when it
accesses an IBM host. The emulator translates the data in the data stream as required
and maps terminal function keys to functions of the IBM 3270. During this phase, the
emulator displays the message “3270 EMULATION MODE” (or a user-defined
message) on line 25 of the screen.
Dual-Application Session
When the terminal accesses a Tandem application, it functions as a Tandem terminal or
Fujitsu 66xx terminal. Which terminal is emulated depends upon the terminal type. In
the case of a personal computer, the terminal emulation mode that is selected depends
upon the type of Tandem, IBM, or Fujitsu terminal the personal computer is emulating.
While accessing the Tandem application, a data-stream translation is not necessary
except when the parameter LINK IBM3270 is used with a Tandem terminal. In this
case, a Tandem-based 3270 data stream is converted to the 6530 data stream.
A switch code in the data stream can initiate the switch to the IBM application, or you
can switch applications with a function key. In either case, the emulator reads and saves
the cursor position and the page buffer number and displays the screen associated with
the new application. This configuration is shown in Figure 1-3.
Note. IBM and Fujitsu terminals do not have a line 25 available for user messages. Therefore,
the information that displays on line 25 of a Tandem terminal is not seen on these types of
devices. However, in some cases, error messages are displayed on line 24 of these terminals.
Figure 1-3. Dual-Application Session
IBM
Host
EM3270
Emulator
EMCOM
Terminal
Access
Method
Tandem
Application
e.g.
Pathway
Terminal
User
Central
Operator
Terminal
S5091-003
TR3271
SNAX/XF
SNAX/CDF
EnvoyACP/XF