Memory and I/O Information
super
MOPS
pro
Copyright
JUMP
tec
Industrielle Computertechnik AG
Page: 12 of 93
Memory and I/O Information
Memory Map
The 24 address lines of the
super
MOPS
pro
processor module can address up to 32MByte of
memory. Onboard DRAM can be up to 32MByte, too (end address 01FFFFFFh). The first 640KByte
of DRAM are used as main memory.
DOS allows to address 1MByte directly. The memory area above 1MByte (high memory, extended
memory) is accessed under DOS via special drivers like HIMEM.SYS, EMM386.EXE etc. Other
operating systems (OS/2, Windows-NT) allow to address the full memory area directly.
Standard Memory Map
0-------------------+ -
¦ Interruptvectors ¦ ¦ 640KByte
¦ BIOS-variables ¦ ¦ of
¦ IO.SYS, MSDOS.SYS ¦ ¦ main memory
¦ COMMAND.COM ¦ ¦
¦ 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)
¦ etc. ¦ ¦
0-------------------¦ ¦ -
¦ System-Setup ¦ ¦ ¦ 64KByte
¦ System-BIOS ¦ ¦ ¦ Shadow RAM
1-------------------¦ + -
¦ ¦ ¦ higher memory area
1-------------------¦ +
¦ ¦ ¦ extended or
¦ ¦ ¦ expanded memory
F-------------------¦ -
¦ System-Setup+BIOS ¦
¦ duplicated ¦
+-------------------+