PRB: Extended INT 13 Doesn't Work in 16-Bit Windows-Based Apps

ID: Q137236

The information in this article applies to:

• Microsoft Windows Software Development Kit (SDK) versions 3.1, 4.0

SYMPTOMS

Extended INT 13 calls in a 16-bit Windows-based application do not work in Windows 95 or Windows 3.1. QuickWin versions of MS-DOS-based applications are the typical cause of this problem. The application works fine as an MS-DOS-based application under Windows 95, but after it is recompiled as a QuickWin application, it fails and possibly causes the program to quit.

CAUSE

The normal INT 13 calls are automatically translated from protected mode to V86 mode by the system (Biosxlat.vxd), but the extended INT 13 calls are not translated and the ROM BIOS is called with an invalid address.

RESOLUTION

Do not execute extended INT 13 calls in 16-bit Windows-based applications. 16-bit Windows applications can use DPMI to call INT 13h functions.

STATUS

This behavior is by design.

Additional reference words: 3.10 4.00 Windows 95 KBCategory: kbprg kbprb KBSubcategory: BseMisc

Last Reviewed: September 27, 1995