Running Paradox 3.5 with EMM386.EXE and MS-DOS 5.0 or later (74188)

The information in this article applies to:
    Microsoft MS-DOS operating system 5.0
    Microsoft MS-DOS operating system 5.0a
    Microsoft MS-DOS operating system 6.0
    Microsoft MS-DOS operating system 6.2
    Microsoft MS-DOS operating system 6.21
    Microsoft MS-DOS operating system 6.22

This article was previously published under Q74188


Borland Paradox version 3.5 does not operate in protected mode when EMM386.EXE installed with the NOEMS switch. Paradox 3.5 can operate in protected mode with EMM386.EXE installed if the RAM switch is used and at least 384K of expanded memory is allocated, as follows:

device=EMM386.EXE 384 RAM


Paradox 3.5 by Borland is an MS-DOS application which can operate either in Real mode or in Protected mode. When operating in Protected mode, Paradox can use Extended memory (using Int15 BIOS calls), or XMS memory (through an XMS memory manager such as HIMEM.SYS). In addition, Paradox complies with the Virtual Control Program Interface (VCPI), which allows a protected-mode application (a VCPI client) to allocate memory being managed by a virtual-86 mode (80386) expanded-memory emulator (a VCPI host), such as EMM386.EXE. If EMM386.EXE (or any VCPI host) is installed, Paradox does not use Extended or XMS memory directly, but instead allocates the memory from the VCPI host (EMM386.EXE). In order for EMM386.EXE to provide this memory to Paradox (or any VCPI-compliant application), EMM386.EXE must be managing that memory.

Loading EMM386.EXE with the RAM switch specifies a pool of memory that EMM386.EXE is to manage, using it to emulate Expanded memory. It is this memory that Paradox (the VCPI client) requests from EMM386.EXE (the VCPI host) for its protected-mode operations. The size of this memory pool must be at least 384 KB for Paradox to operate in protected mode.

NOTE: The README.TXT file from Paradox 3.5 contains the following information on using Paradox 3.5 with 386 expanded memory managers (emulators):

Some EMS emulators can run without allocating an EMS page frame. This lets you use their many extra features, particularly the ability to relocate drivers above 640K, even if you don't want to use EMS. QEMM's FRAME=NONE option has this effect, as does 386Max's NOFRAME option. If you use your EMS emulator this way, you must run Paradox in real mode (this is the mode it will run in by default). Attempting to force Paradox into protected mode in this situation might hang your machine.

The Borland product included here is manufactured by a vendor independent of Microsoft; we make no warranty, implied or otherwise, regarding this product's performance or reliability.

Modification Type: Major Last Reviewed: 5/12/2003
Keywords: KB74188