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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

HP 3000

Bus ness Servers