
Memory and I/O Information
super
MOPS
pro
Copyright
JUMP
tec
Industrielle Computertechnik AG
Page: 13 of 93
Expanded Memory Map
The user can convert (up to 20Mbytes) Extended Memory into Expanded Memory (EMS). The
selected Expanded Memory is devided into 16KByte pages, of which four can be mapped into the
EMS-frame. The EMS-frame is located within the first 1MByte address space and has a length of
64KByte. The start address of the EMS-page can be selected between C8000h and E0000h in steps
of 16KBytes. Most Expanded Memory Managers are choosing their frame address location by
themselves if it is not explicit set..
0-------------------+ -
¦ Interruptvectors ¦ ¦ 640KByte
¦ BIOS-variables ¦ ¦ of
¦ IO.SYS, MSDOS.SYS ¦ ¦ main memory
¦ COMMAND.COM ¦ ¦
¦ HIMEM, EMM386 ¦ ¦
¦ Applications ¦ ¦
0-------------------¦ +
¦ EGA/VGA Video- ¦ ¦
¦ Adapter ¦ ¦ upper memory
0-------------------¦ ¦ area
¦ MGA/CGA Video- ¦ ¦ (RAM areas not
¦ Adapter ¦ ¦ used by video
0-------------------¦ ¦ cards can be -
¦ VGA BIOS ¦ ¦ used otherwise) ¦ 64KByte
0-------------------¦ ¦ ¦ Shadow RAM
¦ BIOS-extensions ¦ ¦ (all not used -
¦ Shadow-RAM ¦ ¦ areas could be
¦ Dual port RAM ¦ ¦ used otherwise)
¦ EMS-Pages ¦ ¦
¦ etc. ¦ ¦
0-------------------¦ ¦ -
¦ System-Setup ¦ ¦ ¦ 64KByte
¦ System-BIOS ¦ ¦ ¦ Shadow RAM
1-------------------¦ + -
¦ ¦ ¦ higher memory area
1-------------------¦ +
¦ ¦ ¦ extended or
¦ ¦ ¦ expanded memory
F-------------------¦ -
¦ System-Setup+BIOS ¦
¦ duplicated ¦
+-------------------+
To be able to work with Expanded Memory under MS-DOS, you have to add the following drivers to
your CONFIG.SYS:
HIMEM.SYS and EMM386.EXE
The
superMOPSpro
uses a 32KByte extension BIOS (many other boards do this, too) which is
mapped to a configurable memory area. Some other kind of boards have no extension BIOS, but are
using drivers which communicate with their corresponding devices via memory mapped I/O. All these
boards have one thing in common, they have to share the upper memory area with the Expanded
Memory Manager. This is often the reason for several problems in the system. Make sure you
excluded all areas in the upper memory, which are used by extension BIOSes and memory mapped
I/O. Your instruction in the CONFIG.SYS concerning the Expanded Memory Manager should look like
this: (questionmarks for location of extension BIOS)
DEVICE=EMM386.EXE X=
????-????
X=F000-FFFF