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- OSDAMEM - PROBLEMS RUNNING DOS APPLICATIONS IN A VDM
- 10/19/94
-
- ================================================================
- PROBLEMS RUNNING DOS APPLICATIONS IN A VDM
- ================================================================
-
- Please Read Entire Document For Full Explanation of Procedure
- ----------------------------------------------------------------
-
- SYMPTOMS:
- DOS applications running in a VDM may have problems with
- expanded memory conflicts (EMS), SYS3176, and session locks up.
-
-
- RESOLUTION:
- Many DOS applications, TSRs, or loading device drivers high,
- use Expanded Memory (EMS) when loading. Some examples of DOS
- applications are spreadsheets, wordprocesssors, databases,
- desktop publishing, and CAD systems. Several problems can
- occur if EMS is not detected:
-
- 1. SYS3176 error.
- 2. The VDM session locks up when starting up the application.
- 3. When starting up the application in a VDM, a flash of text
- relating to an adapter conflict appears before it closes
- and goes back to OS/2 desktop. It goes by so fast, you
- can hardly see it.
-
- TSR (Terminate-and-Stay-Resident)
- A VDM closes when it detects the TSR terminating, so there
- is no chance for it to become resident. To load a TSR you
- must make a Desktop Program Object from Templates Folder.
-
- On the Program page of the Settings Notebook:
- A. Type: * in PATH and FILENAME field if it does not appear
- B. Complete the parameters field with /K followed by the
- PATH and program name of the TSR. For example:
- /K C:\FT\FTTERM.BAT
- See Vol. 2, Page 200, IBM Redbooks for more information.
-
- 4. Very little expanded memory shows up in the application no
- matter what changes were made to the DOS Settings. To
- configure EMS support for the OS/2 Virtual DOS Machine
- (VDM), a contiguous 64KB block of RAM is used as the EMS
- Page Frame and must be available with the Upper Memory
- Block (UMB) between 640KB and 1MB. That address range is
- between C0000-CFFFF which is exactly 64KB of memory.
-
- We recommend remapping to the D0000-DFFFF range all adapter
- cards whose ROM and RAM addresses are mapped between the
- C0000-CFFFF range. The most common adapter cards are
- video, network, modem, and emulation. Many IBM and OEM
- systems have their Token Ring Adapter cards mapped to
- the C0000-CFFFF region.
-
- ================================================================
-
- ADDITIONAL INFORMATION FOR EMS MEMORY
-
- EMS MEMORY AND CONFLICTS WITH ADAPTER MEMORY
-
- Expanded Memory uses memory addresses that sometimes conflict
- with adapters. EMS needs 64k of contiguous space before it
- can install. The more adapters you have, the more likely
- the conflict. Network, disk, and 3270 adapters usually have
- memory present which can prevent EMS activation.
-
- There are two techniques to stop the conflict.
-
- ONE:
- Use the INCLUDE property MEM_INCLUDE_REGIONS. With this
- property, you can disable the adapter memory for only that
- session and allow EMS to use it instead.
-
- EXAMPLE: If you have a 3270 adapter, and already have OS/2
- Comm Manager support, you do not need to use the 3270 memory
- in a DOS session. To disable the memory in a DOS session,
- you need to find the address of the 3270 adapter, by using
- the reference diskettes on PS/2's. When the address is
- known, specify the range in the INCLUDE property. Most
- IBM 3270 adapters start at CE000 (0XCE00 absolute). The
- property should be set to:
-
- CE000-CFFFF
-
- This allows EMS to use this memory if there is enough memory
- near this range.
-
- TWO:
- Change addresses of the adapters with the reference diskette.
-
- EXAMPLE: On a PS/2 Model 80 ESDI with both a Token Ring and
- 3270 adapter, it is necessary to change the defaults to
- enable EMS.
-
- NOTE: The '0x' prefix on numbers means it is hexadecimal.
-
- Address Use Address Name Length (in KBytes)
- ------------ ------------ ------------------
- VGA (Video) 0xA0000-0xBFFFF 128K
- Not in Use 0xC0000-0xC7FFF 32K (Free)
- ESDI Adapter (Disk) 0xC8000-0xCBFFF 16K
- IBM Token Ring ROM 0xCC000-0xCDFFF 8K
- IBM 3270 Adapter 0xCE000-0xCFFFF 8K
- Not in Use 0xD0000-0xD7FFF 32K (Free)
- IBM Token Ring RAM 0xD8000-0xDBFFF 16K
- Not in Use 0xDC000-0xDFFFF 16K (Free)
- PS/2 ROM 0xE0000-0xFFFFF 128K
-
- To use a DOS network redirector and a DOS 3270 driver in the
- same session with EMS memory, re-arrange the addresses of the
- adapters that allow a 64k sized window into the range from
- 0xA0000 to 0xFFFFF. Since you need both VGA and PS/2 ROM,
- the range has to be between 0xC0000 and 0xDFFFF.
-
- There is a total of 80k free in that range, it just is not
- contiguous. The goal is to make it contiguous.
-
- Use the PS/2 Reference diskette to change the addresses of the
- adapters. In this case, it is best to move the adapters
- from the 0xC0000-0xCFFFF range into the 0xD0000-0xDFFFF range.
-
- Move ESDI ROM to 0xD0000
- Move Token-Ring ROM to 0xD4000
- Move 3270 RAM to 0xD6000
-
- The new map would look like:
-
- Address Use Address Name Length (in KBytes)
- ------------ ------------ ------------------
- VGA 0xA0000-0xBFFFF 128K
- EMS Memory 0xC0000-0xCFFFF 64K (EMS Range)
- ESDI Adapter 0xD0000-0xD3FFF 16K
- IBM Token Ring ROM 0xD4000-0xD5FFF 8K
- IBM 3270 Adapter 0xD6000-0xD7FFF 8K
- IBM Token Ring RAM 0xD8000-0xDBFFF 16K
- Not in Use 0xDC000-0xDFFFF 16K (Free)
- PS/2 ROM 0xE0000-0xFFFFF 128K
-
- The memory not in use for EMS could be used by the XMS Upper
- Memory Blocks. The 16k could be used by OS/2 DOS to load a
- device driver or TSR high.
-
- ================================================================
-
- RECONFIGURING THE MEMORY REMAPPING ON VARIOUS MACHINES
-
- IBM SYSTEMS
- ------------
- Some of the IBM hardware systems: 56 SLC, 57 SLC, 56 SLC2,
- 57 SLC2, 76, 77, and 90, have a built in utility program to
- create a backup Reference diskette. The diagnostics to
- reconfigure the register addresses is run from the hard
- disk. Most of these systems have their video adapter
- cards mapped to the C0000-CFFFF region.
-
- To start the Utility Program from the hard disk:
- 1. Turn on the computer and let the self-tests complete.
- 2. Press Ctrl+Alt+Del. Watch the cursor closely, and when it
- moves to the top-right corner of the screen.
- 3. Press Ctrl+Alt+Ins. See IBM Reference Diskette Instructions
- below.
-
- IBM VALUE POINT
- ---------------
- These systems have their video addresses mapped to the
- A0000-AFFFF range. These also have to start the utility
- program from the hard disk. See instructions from IBM
- Preloads above.
-
- OTHER IBM PS/2 MICRO CHANNEL SYSTEMS
- ------------------------------------
- A Reference Diskette is supplied with each system. Start
- the diskette from Drive A:. See IBM Reference Diskette
- Instructions below.
-
- IBM REFERENCE DISKETTE INSTRUCTIONS
- When the IBM logo appears:
- 1. Press Enter and select Set Configuration.
- 2. Select Change Configuration
- 3. Select the slot and location of the adapter card that is
- mapped to the C0000-CFFFF range.
- 4. Use PF6 to toggle up or down to a free D0000-DFFFF memory
- range address.
- 5. Press PF10 to Save the configuration.
- 6. Restart the machine. The goal is to free the C0000-CFFFF
- address range by moving adapter ROM and RAM addresses to
- the D0000-DFFFF range.
-
- EISA/ISA BUS ARCHITECTURE SYSTEMS
- Many of these systems have a built in Diagnostics Setup and
- Configuration file. After starting, the screen displays a
- sequence of keys to press to display the Setup. Some
- systems allow only viewing and some allow viewing and
- reconfiguring. Quite a few adapter cards can only be
- reconfigured by resetting dip switches on the card. Refer
- to the manufacturer's documentation that came with the card,
- or contact the vendor where you purchased the system.
-
- ----------------------------------------------------------------
- IBM disclaims all warranties, whether express or implied,
- including without limitation, warranties of fitness and
- merchantability with respect to the information in this document.
- By furnishing this document, IBM grants no licenses to any
- related patents or copyrights.
-