Article: Q105275
Product(s): Microsoft Windows Software Development Kit
Version(s): WINDOWS:3.0,3.1
Operating System(s):
Keyword(s): kb16bitonly
Last Modified: 05-NOV-1999
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The information in this article applies to:
- Microsoft Windows Software Development Kit (SDK) versions 3.0, 3.1
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SUMMARY
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The "BR" command in WDEB386.EXE uses the debug registers of the Intel 386 and
above processors to break into the debugger on memory accesses. These accesses
can be in byte, word, or dword sizes involving a read, write, or execute
instruction. Because the BR command is very specific as to the type of memory
access it will trap, care must be taken to choose the correct combination of BR
settings in order to obtain all possible cases:
E == execute access
W == write access
R == read access
1 == byte sized access
2 == word sized access
4 == dword sized access
When a break into the debugger is required when a memory location is modified,
set a few BR breakpoints on a Write operation giving the three different operand
sizes:
BR W1 seg:off
BR W2 seg:off
BR W4 seg:off
This should cover all possible cases of the memory being touched.
Additional query words: 3.10 no32bit 3.00 breakpoint br
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Keywords : kb16bitonly
Technology : kbAudDeveloper kbWin3xSearch kbSDKSearch kbWinSDKSearch kbWinSDK300 kbWinSDK310
Version : WINDOWS:3.0,3.1
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