DOS

Purpose:    Makes DOS to load itself into the HMA on PCs with 286+
            processors, also instructs DOS to use or not to use the upper
            memory area (UMB).

Syntax:     DOS = < [HIGH|LOW] [UMB|NOUMB] >

By default: DOS = LOW,NOUMB

Note:
     Use this command to increase the size of the free lower memory.

     Options HIGH and LOW define whether DOS will use the 64K HMA or not.
This option requires installation of a XMS server. The PTS-DOS package
includes two XMS support drivers - Himem286.Sys and Himem386.Sys for 286 and
386+ processors, respectively.

     Options UMB and NOUMB define whether DOS will use the UMB blocks or
not. When DOS=UMB, a TSR or a driver may be installed into the UMB using the
DEVICEHIGH=, INSTALLHIGH= commands or with the LOADHIGH DOS command.  The
option requires installed UMB server, e.g. EMM386, 386MAX, QEMM386.

     Options may be used combined in a single line. Line:
     DOS=HIGH,UMB
is equivalent to the lines:
     DOS=HIGH
     DOS=UMB