Q76820 - Programs Don't Load into Upper Memory Area

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Programs Don't Load into Upper Memory Area

The information in this article applies to:

Microsoft MS-DOS operating system version 5.0

SYMPTOMS

You set up your system to run device drivers and programs in the upper memory area, but when you use the MEM /C command, nothing appears in the Upper Memory Area section of the MEM command output.

CAUSE

There are several things that can cause these symptoms:

You are running Windows version 3.0 in 386 enhanced mode and issued the MEM /C command from the MS-DOS command prompt while Windows was running. The MEM command does not report the contents of the upper memory area when Windows is running in 386 enhanced mode.

Your system might not be set up properly to run programs in the upper memory area. To make sure your system is set up properly, see "Making Sure Your System Is Set Up to Run Programs in the UMA" in this document.

You are starting EMM386 with the RAM switch, which allows you to use expanded memory. The RAM switch sets aside 64K of the upper memory area for use as an expanded-memory page frame. This might not leave enough space in the upper memory area to load any programs or device drivers. To solve this problem, see "Adjusting EMM386 to Provide More Upper Memory Blocks" later in this document.

MAKING SURE YOUR SYSTEM IS SET UP TO RUN PROGRAMS IN THE UMA

You should be able to run programs in the upper memory area (UMA) if all the following conditions are met:

Your computer must have an 80386 or higher processor.

Your computer must have at least 350K of extended memory available.

Your CONFIG.SYS file must contain a DEVICE command for HIMEM.SYS. This command must appear before any other DEVICE commands or DEVICEHIGH commands.

Your CONFIG.SYS file must contain either a DOS=UMB or DOS=HIGH, UMB command.

Your CONFIG.SYS file must contain a DEVICE command for EMM386.EXE, which must include either the NOEMS switch or the RAM switch. This command must appear after the DEVICE command for HIMEM.SYS, but before any DEVICEHIGH commands.

Your CONFIG.SYS file must contain a DEVICEHIGH command for each device driver you want to load into the upper memory area.

Your AUTOEXEC.BAT file should contain a LOADHIGH command for each memory-resident program you want to run in the upper memory area.

The following sample CONFIG.SYS file contains examples of the commands you need to run programs in the upper memory area:


   device=c:\dos\himem.sys

   dos=high,umb

   device=c:\dos\emm386.exe ram

   devicehigh=c:\util\mydriver.sys

For instructions on setting up your system to run programs in the upper memory area, see page 317 of the "User's Guide and Reference."

ADJUSTING EMM386 TO PROVIDE MORE UPPER MEMORY BLOCKS

You can adjust EMM386 so that it provides additional space in the upper memory area for use as upper memory blocks (UMBs). (This is particularly useful if you are starting EMM386 with the RAM switch.) First, complete the steps in Procedure 1. If you still cannot load programs and device drivers into UMBs, complete the steps in Procedure 2.

Procedure 1: Including Specific Portions of the Upper Memory Area

Certain addresses in the upper memory area are normally reserved for use by hardware and video drivers; EMM386 does not usually make these areas available as UMBs. However, on many systems, the hardware and video drivers do not use all the reserved memory addresses. The remaining addresses can be included by EMM386 for use as UMBs. To instruct EMM386 to include these unused areas, you use the I switch after the DEVICE command that starts EMM386.

To allocate additional space in the upper memory area for use as UMBs, follow these steps:

Create an MS-DOS version 5.0 startup disk. To do so, insert a formatted floppy disk in drive A and type the following:
sys c: a:

Copy your CONFIG.SYS file to the startup disk by typing the following:
copy c:\config.sys a:\

Edit your original CONFIG.SYS file. To edit the file using MS-DOS Editor, type the following at the command prompt:
edit c:\config.sys

Locate the DEVICE command for EMM386.EXE, and insert the I switch in front of the RAM or the NOEMS switch. The I switch specifies a range of addresses in the upper memory area, and tells EMM386 to allocate that memory for use as UMBs. The value you specify for the I switch will depend on your computer and monitor type.
- If your computer is not an IBM PS/2 and does not have a monochrome monitor, add the i=E000-EFFF and the i=B000-B7FF switches before the RAM or NOEMS switch, as follows:
```
        device=c:\dos\emm386.exe i=E000-EFFF i=B000-B7FF ram 
```
- If your computer is not a PS/2 and has a monochrome monitor, add the i=E000-EFFF switch before the RAM or NOEMS switch, as follows:
```
        device=c:\dos\emm386.exe i=E000-EFFF ram 
```
- If your computer is an IBM PS/2 and does not have a monochrome monitor, add the i=B000-B7FF switch before the RAM or NOEMS switch, as follows:
```
        device=c:\dos\emm386.exe i=B000-B7FF ram 
```
- If your computer is an IBM PS/2 with a monochrome monitor, see Procedure 2.

If you're using MS-DOS Editor, choose Exit from the File menu. When MS-DOS Editor displays a dialog box prompting you to save your file, choose Yes, or press ENTER.

Restart your computer by pressing CTRL+ALT+DEL.

If your computer fails when you start it, the memory range you specified for EMM386 is probably being used by hardware or video display drivers. In that case, insert your startup disk in drive A and restart your computer. Then, edit your CONFIG.SYS file and remove the I switch(es) you added to the DEVICE command for EMM386.

If you are starting EMM386 with the RAM switch, follow Procedure 2. Otherwise, contact Microsoft Support Services for further assistance.

After your computer starts, check whether your programs were loaded into UMBs successfully. To do so, type the following at the command prompt:
mem /c |more
This command displays the contents of your computer's conventional and upper memory, and shows where in memory each program is running. (For more information about the MEM command and UMBs, see page 320 of the "User's Guide and Reference.")

You have solved the problem if your programs and device drivers are running in UMBs.

If you still cannot load your programs into UMBs, your system might be using much of the upper memory area for hardware code. Some computers use the upper memory area for ROM shadowing, which can improve your computer's speed. (In ROM shadowing, the computer copies hardware code from the slower read-only memory (ROM) into the faster RAM.) To find out more about how your computer uses the upper memory area, see the documentation that came with it.

If you cannot load programs into UMBs and you are starting EMM386 with the RAM switch, follow the steps in Procedure 2.

Procedure 2: Reducing the Space Set Aside for Use with Expanded Memory

If you start EMM386 with the RAM switch and programs or device drivers do not load into UMBs when your computer starts, there might not be enough UMBs to run those programs. This is because using the RAM switch sets aside 64K of the upper memory area as a page frame for use with expanded memory. The remaining UMBs might not be large enough to run your programs, even if you were able to include additional addresses by following Procedure 1.

You can instruct EMM386 to set aside 16K of the upper memory area, rather than 64K, as an expanded-memory page frame. This makes more UMBs available.

NOTE: Use this procedure only if your applications use expanded memory according to the Lotus-Intel-Microsoft Expanded Memory Specification (LIM EMS) version 4.0. Applications that follow the LIM EMS version 3.2 need the full 64K page frame, and will not be able to use expanded memory if you follow this procedure.

To reduce the number of UMBs set aside for use with expanded memory, follow these steps:

Type the following at the MS-DOS command prompt:
emm386
EMM386 displays information about its current memory-management activities. Locate the line that reads "Page frame segment" and write down the hexadecimal address that appears on that line. In the following example, the page frame segment address is E000.
```
      Page frame segment . . . . . . . . . E000  F 
```

Edit your original CONFIG.SYS file. To edit the file using MS-DOS Editor, type the following at the MS-DOS command prompt:
edit c:\config.sys

Locate the DEVICE command for EMM386.EXE, and insert the P0 switch before the RAM switch. The P0 switch should specify the address you obtained from EMM386 in Step 1. For example, if the page frame segment was E000, the DEVICE command would appear as follows:
```
      device=c:\dos\emm386.exe p0=E000 ram 
```

If you're using MS-DOS Editor, choose Exit from the File menu. When MS-DOS Editor displays a dialog box prompting you to save your file, choose Yes or press ENTER.

Restart your computer by pressing CTRL+ALT+DEL.

If your computer fails when you start it, insert your startup disk in drive A and restart your computer. Then, edit your CONFIG.SYS file and remove the P0 switch you added to the DEVICE command for Procedure 2; be sure to check the page frame segment address carefully.

After your computer starts, check whether your programs were loaded into UMBs successfully. To do so, type the following at the MS-DOS command prompt:
mem /c |more
This command displays the contents of your computer's conventional and upper memory, and shows where in memory each program is running. (For more information about the MEM /C command and UMBs, see page 320 of the "User's Guide and Reference.")

You have solved the problem if your programs and device drivers are running in UMBs.

If your programs are still not running in UMBs, contact Microsoft Support Services for further assistance.

REFERENCES

See the following for additional information:

"User's Guide and Reference," pages 313-326, explains how to set up your computer to run programs in the upper memory area.

"User's Guide and Reference," page 327, explains how to troubleshoot the process of running programs in the upper memory area.

"User's Guide and Reference," page 435, provides information about the DEVICEHIGH command.

"User's Guide and Reference," page 518, provides information about the LOADHIGH command.

"User's Guide and Reference," page 519, provides information about the MEM command.

"User's Guide and Reference," page 605, provides information about EMM386.EXE startup parameters.

"User's Guide and Reference," page 610, provides information about HIMEM.SYS startup parameters.

Additional query words: appnote 5.00

Keywords : msdos
Version : MS-DOS:5.0
Platform : MS-DOS
Issue type :
Technology :

Article ID: Q76820

Last Reviewed:
November 16, 1999

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