Programs that were originally developed on MPE/V must be rewritten
to run in native mode on the MPE/XL. For details, refer to the following
reference manuals:
Migration Process Guide describes how to migrate existing applications to
MPE/XL.
Programmers' Skills Migration Guide explains new program development on MPE/XL and serves
as a reference to the operating system.
COBOL II/XL Migration Guide explains how to migrate COBOL II/V programs to MPE/XL.
FORTRAN 77/XL Migration Guide, details the migration of FORTRAN 77/V applications
to MPE/XL.
HP Pascal/XL Migration Guide details the migration of Pascal applications to MPE/XL.
Migration of SPL programs to MPE/XL.
Some points to be noted when applications developed on VPLUS
are run MPE/XL are described below.
Terminals. When you run an application
on MPE/XL, the terminal must be configured for the XON/XOFF handshake. If it is not, large or complex forms
will appear to be corrupted when displayed on the screen.
Floating Point Numbers. The type conversion
of floating point numbers in VPLUS assumes the HP 3000 floating
point format, whereas native mode applications store floating point
values in IEEE format. The type conversion will work, but the values
will be wrong.
Native Mode Pascal Applications. The
MPE/XL native mode Pascal compiler allocates 4 bytes for the integer
subrange -32768..32767, compared with the 2 bytes allocated by the MPE/V
pascal compiler. You should use type SHORTINT in native mode Pascal applications to get a 2-byte
allocation for this subrange.
Record padding in native mode Pascal will cause data misalignment
problems for programmers using the VPLUS intrinsics, VGETFIELDINFO, VGETFORMINFO, and VGETFILEIINFO. The problem can be avoided by packing the inforbuf records passed as parameters.
Incorrect Parameters. Existing VPLUS
applications written in COBOL and recompiled into MPE/XL native
mode may fail to function. The application either fails with VPLUS error
code of 998 or 999, or it aborts with a Memory Fault error. The
reason for this is that the programmer has coded the application
to pass a display numeric data type as the parameter for a VPLUS
intrinsic, instead of a binary numeric data type. That is, COBOL data
type PIC 9 has been coded instead of PIC 9 COMP.
This kind of mistake is not caught when the application is
compiled, because most COBOL VPLUS applications do not use the compiler
intrinsic mechanism, "CALL INTRINSIC...USING...".
So, the error must be caught at run-time, if at all. It is possible for
the defective program to appear to work correctly in MPE/V and MPE/XL
compatibility mode, because VPLUS is more forgiving when parameters
of the wrong type are passed to it. However, native mode applications
on MPE/XL call the VPLUS intrinsics through switch stubs, which
require the correct parameter types. The wrong parameter causes
a run-time error because the VPLUS native mode access layer does
not have the capacity to edit the data passed through it.
If your application fails with a VPLUS error 998 or 999, or
a memory fault, you can take the following steps:
Activate the VPLUS trace facility and examine the trace, especially
the entering and leaving messages from the VPLUS native mode stub
software.
Check the parameter content messages of the last
VPLUS intrinsic call before the program failed.
Examine and correct VPLUS parameter declarations
as needed, both in native mode code and in compatibility mode code
if this is a migrated application.
Supported Peripherals and Applications |
 |
The following are currently supported on MPE/XL.
Printers-HPIB 2565, 2566, 2680, 2688
Terminals 2392, 2393, 2394, 2397,
2622, 2624B, 2627,
HP 150, Vectra, Port+
Native Mode COBOL II/XL, FORTRAN 77/XL
Languages HP Pascal/XL
Compatibility Mode SPL/V RPG/V, Business BASIC/V,
Languages Transact/V |
