Native Mode (NM) because SPL/V has a high dependence on the MPE V/E-based HP 3000 architecture. However, you can improve the performance of an SPL/V application running in CM by using the MPE V/E Object Code T ranslator.

If you require NM performance, these applications should be rewritten in HP C/iX or HP Pascal/iX, which are systems programming languages for MPE/iX. If an application written in a high-level language calls SPL/V procedures, y ou can recompile it in NM. It runs in NM and uses a user-supplied mode switc hing procedure to switc h to CM to call SPL procedures.

For information on less frequen tly encountered exceptions, refer to the Migration Series of manuals. For information on switc hing, refer to Switch Programming Guide (32650-90014).

Cross-family Application Development

You can develop applications on a 900 Series system for use on HP 3000 systems that use HP Precision Architecture (HP-PA) by using a 900 Series for cen tralized development. You can compile the source code for programs written to run on a Native Mode compiler on the 900 Series system and compile it to run on MPE V/E-based systems.

Similarly, you can compile source code written to run in Compatibility Mode on the 900 Series and compile it to run on MPE V/E-based systems. The MPE V Segmen ter is supplied with MPE/iX to facilitate cross-family dev elopment in these languages.

MPE/iX Features

The main features of the MPE/iX operating system on a 900 Series computer include:

Multiprogramming: concurren t transaction processing, data comm unications, on-line program dev elopment, and batch processing.

Extended large addressing: 48-bit virtual addressing.

Demand paged virtual memory , which transparently manages virtual memory and eliminates the need for program segmen tation.

Mapped disc ￿les, whic h eliminates the need for File System bu￿ering for disc ￿les. This increases system performance for I/O-in tensive applications.

Concurrent multilingual capability , including HP-extended v ersions of C, COBOL, RPG, FORTRAN, BASIC, and Pascal.

File System, whic h includes ￿le backup, user logging, securit y, and interprocess communication (IPC).

Access security and complete accoun ting resources.

Command interpreter, which includes user-de￿ned commands (UDCs), command ￿les, conditional job con trol, extensiv e on-line help facility, and descriptive error messages.

Device and ￿le independence, whic h simpli￿es application dev elopment and maintenance.

I/O System, whic h provides input/output spooling and a tape label facilit y.

Complete, automatic local and remote terminal managemen t. Power fail/automatic restart.

OVERVIEW 1-7