HP3000
Bus ness
Servers
Functional Description
HP SNA DHCF/iX is a software product that
provides an IBM 3270 display station with
access to applications on an HP 3000. SNA
DHCF/iX emulates many features of a
remotely attached HP terminal; thus, it
appears as if the IBM 3270 display station has
a direct connection to the HP 3000 computer.
SNA DHCF/iX can be operated across an
existing SNA or X.25 network.
SNA DHCF/iX communicates with Host
Command Facility (HCF) on the IBM
mainframe in order to exchange data between
the user’s MPE session and the IBM terminal.
To the HP 3000 system, each SNA DHCF/iX
session appears as a NS VT session. For IBM
3270 display stations, SNA DHCF/iX provides
access to two primary groups of applications
on the HP 3000 Series 900 system.
• TTY-mode applications are characterized by
their simple use of terminal control charac-
ters (carriage return, line feed, form feed,
tab, bell). SNA DHCF/iX translates the data
as output being sent to the IBM terminal.
This group of applications includes the basic
MPE/iX CI (Command Interpreter) com-
mands.
• VPLUS applications are characterized by
the use of the VPLUS forms subsystem that
is included with the MPE FOS. VPLUS has
been enhanced so that an applications pro-
grammer can design VPLUS-based applica-
tions for the IBM 3270 display station in
addition to other HP terminals.
Consequently, IBM 3270 display station
users can be provided with access to many
VPLUS-based applications using SNA
DHCF/iX.
When developing VPLUS applications for use
with SNA DHCF/iX, the application designer
can develop and modify VPLUS forms using
techniques similar to those for HP terminals.
When the VPLUS forms have been designed
and are ready to be compiled, the applications
designer will select the “IBM 3270” box in the
Terminal Selection Menu of FORMSPEC, in
addition to any HP terminal options normally
selected, in order to include the IBM 3270
format in the VPLUS forms file. Please note
that, in an existing application, some VPLUS
forms may need to be modified due to
limitations of the IBM 3270 display station.
Many of the VPLUS forms may require no
changes.
Usage Considerations
HP SNA DHCF/iX is not a complete
replacement for HP terminals such as the HP
700/92 and HP 700/94 terminals. Due to
limitations of the IBM 3270 display station,
SNA DHCF/iX cannot support all HP 3000
applications. In addition, some HP 3000
applications may require modifications prior
to use with SNA DHCF/iX. Please refer to the
SNA DHCF/iX Application Programmer’s
Guide for information on usage considerations
discussed here.
The HP keyboard differs from the IBM
keyboard. The chart below shows some
differences.
HP Terminals
IBM Terminals
HP Function Keys
IBM PF Keys 1-8 (VPLUS
Applications only)
Security fields,
Equivalent functions provided
Full-Bright and
Half-Bright fields
Previous Page Key,
No equivalent functions
Next Page Key,
provided for IBM terminals
Insert Line Key, and
Delete Line Key
HP terminal characters: IBM Terminal mapping:
Break
PA1
Control-Y
PA2
Hard RESET
CLEAR
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