20
HP 3000 applications that use special screen- mode or
•HP terminal escape sequences used for cur- sor positioning, terminal strap settings, pro- grammable softkeys, etc.
•Screen enhancements such as inverse video, blinking, underlining, etc.
SNA DHCF/iX can provide universal access to HPDESK for an integrated office automation solution.
Within VPLUS applications, SNA DHCF/iX supports all of the VPLUS intrinsics except for VPRINTSCREEN and VPRINTFORM. Due to limitations of the IBM 3270 display station, VPLUS forms caching is not supported with SNA DHCF/iX. In addition, several points need to be considered in VPLUS forms design including:
•Prior to using a VPLUS application with SNA DHCF/iX, the VPLUS forms file must be recompiled using the ‘IBM 3270’ terminal option.
•When using FORMSPEC to design VPLUS forms, an HP terminal such as the HP 700/94 is required.
•Unlike HP terminals, IBM 3270 display sta- tions require an actual space on the screen for an attribute byte that describes the attributes of the following field.
•Each field on the IBM display station needs to be preceded by this attribute byte; conse- quently,
•With SNA DHCF/iX, a VPLUS form can have at most 24 lines; if features such as softkeys (two lines) or a window line (one line) are used in the application, then the available lines for the form are reduced by the num- ber of lines required by these features.
If the target application violates any of these restrictions, then it is not supported by SNA DHCF/iX. An error condition will be returned to the application when an unsupported feature is used. Prior to installation of SNA DHCF/iX, target HP 3000 applications should be qualified to ensure that they meet these restrictions.
When using SNA DHCF/iX, IBM 3270 display station users may experience different performance and functionality than HP terminal users. For IBM 3270 display stations, response times may be somewhat greater than an HP terminal due to the SNA network overhead.
Functional Specifications
•SNA DHCF/iX supports many of the basic functions of HP terminals. Please refer to the Usage Considerations section for fea- tures that are not supported. Supported fea- tures include:
–Modified Data Tags
–Security Fields
•SNA DHCF/iX supports three different dis- play enhancements for IBM 3270 display stations:
•SNA DHCF/iX supports those IBM devices officially supported by IBM for the Host Command Facility, Version 2. Please refer to IBM’s HCF Product Specification Guide
•Each SNA DHCF/iX session appears as a Virtual Terminal session. The pool of Virtual Terminal sessions available for other users will be reduced by the number of SNA DHCF/iX sessions that are currently active.
•SNA DHCF/iX can support multiple simulta- neous sessions, depending upon the number of VT sessions or LDEVs (depending on the MPE/iX release) distributed across multiple SNA Links.
•Each SNA Link can support up to 64 con- current sessions distributed among the vari- ous SNA/iX services.
HP 3000
