Debug: xa (allocate expanded memory)

Allocates a specified number of pages of expanded memory. Used without parameters, xa checks for the presence or absence of extended memory support (EMS).




count : Specifies the number of 16-kilobyte pages of expanded memory to allocate.

?: Displays a list of debug subcommands.


Windows XP does not use this command. It is accepted only for compatibility with MS-DOS files. 

Windows XP does not support EMS. To use expanded memory, you must install an expanded memory device driver that conforms to version 4.0 of the Lotus/Intel/Microsoft Expanded Memory Specification (LIM EMS).

If the specified number of pages is available, Debug.exe displays a message indicating the hexadecimal number of the handle that is created. Otherwise, Debug.exe displays an error message.


To allocate eight pages of expanded memory, type:


If the command is successful, Debug.exe displays a message similar to the following:

Handle created=0003

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Information that the user must supply


Elements that the user must type exactly as shown

Ellipsis (...)

Parameter that can be repeated several times in a command line

Between brackets ([])

Optional items

Between braces ({}); choices separated by pipe (|). Example: {even|odd}

Set of choices from which the user must choose only one

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Code or program output

Debug subcommands

Debug: xd (deallocate expanded memory)

Debug: xm (map expanded memory pages)

Debug: xs (display expanded memory status)

Command-line reference A-Z

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