Loading MS-DOS High on Zenith SuperSport 286 with 1 MB RAM (77210)

The information in this article applies to:
    Microsoft MS-DOS operating system 5.0
    Microsoft MS-DOS operating system 5.0a
    Microsoft MS-DOS operating system 6.0
    Microsoft MS-DOS operating system 6.2
    Microsoft MS-DOS operating system 6.21
    Microsoft MS-DOS operating system 6.22

This article was previously published under Q77210


If you have a Zenith SuperSport 80286 computer with 1 MB of memory, you may not be able to load MS-DOS 5.0 or later into the high memory area (HMA).


This is not a limitation of MS-DOS 5.0 or later, but an incompatibility with the hardware design of the Zenith SuperSport 80286.


The Zenith SuperSport 80286 with 1 MB of memory is configured for 640K base, 128K for video/ROM BIOS, and 256K reserved for expanded memory. With this hardware design, contiguous extended memory is not present for MS-DOS to load into the HMA.

Expanded memory can be accessed through the expanded memory manager provided by Zenith Data Systems. This memory manager would be loaded in the CONFIG.SYS file as follows:
Without the use of this driver, expanded memory services are unavailable, and 256K of memory will not be used. This memory cannot be reconfigured as extended memory.

Modification Type: Major Last Reviewed: 5/12/2003
Keywords: KB77210