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Q71264: Information on SYSTEM.INI [386enh] Entry SystemROMBreakPoint=

Article: Q71264
Product(s): Microsoft Windows 95.x Retail Product
Version(s): WINDOWS:3.0,3.0a,3.1,3.11
Operating System(s): 
Keyword(s): 
Last Modified: 21-SEP-1999

3.00 3.00a 3.10 3.11

WINDOWS

kbref kbenv

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The information in this article applies to:

- Microsoft Windows versions 3.0, 3.0a, 3.1, 3.11 
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SUMMARY
=======

The following is information about the SYSTEM.INI [386Enh] entry
SystemROMBreakPoint=.

The first section is taken from the Windows SYSINI3.TXT file. Below that, you
find more specific information on Windows' relationship with
SystemROMBreakPoint=.

MORE INFORMATION
================

SYSINI3.TXT
-----------

SystemROMBreakPoint=<Boolean>

Default: True
Purpose: Specifies whether Windows should use ROM address
        space between F000:0000 and 1 MB for a break
        point. Windows in 386 enhanced mode normally
        searches this space to find a special instruction
        that is used as a system break point. If this
        address space contains something other than
        permanently available ROM, you should disable
        this setting.

To change: Use Notepad to edit the SYSTEM.INI file.

Windows is searching for a byte value equal to 63H, which is an adjust-requested
privilege level (ARPL) instruction in the range F000-FFFF.

When the SystemROMBreakPoint variable is set to false, enhanced mode Windows
allocates a one-byte block of global virtual 8086 memory in low MS-DOS
conventional memory and writes a 63h in it.

With QEMM and 386Max, SystemROMBreakPoint= must be set to false. These expanded
memory emulators remap the ROM. The search in the system ROM for the system ROM
break point must be disabled if the ROM is going to be remapped.

Additional query words: 3.00 3.00a 3.10 3.11 winmem \* yeswin4

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Keywords          :  
Technology        : kbWin3xSearch kbZNotKeyword3 kbWin300 kbWin300a kbWin310 kbWin311
Version           : WINDOWS:3.0,3.0a,3.1,3.11

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