Datatech Enterprises 386/25, User Manual

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Shadow RAM
For higher performance, the PEM-2530 has two shadow RAM func-
tions. We have released DTK and Phoenix (under the authorization of
Phoenix) BIOS, and one program on a diskette for your convenience.
Shadow RAM is one of the advanced features of the PEM-2530. Your
BIOS or diskette will support the following:
•
A 64KB DRAM space allocated for BIOS shadow RAM
•
A 64KB DRAM space allocated for video shadow RAM
BIOS and video addresses are allocated for shadow RAM. Both
sections are 64KB in size. Refer to the table below for more informa-
tion.
Figure 2-9: Address Map of BIOS and video
Note:
•
If the working area of your package or add-on card (execpt
video card) is located between addresses C0000H-
CFFFFH, you must disable the video shoadow RAM to
avoid an address conflict.
•
A reserved 128K DRAM space is allocated for shadow
RAM. You cannot use it for another purpose even if these
functions are disabled. Refer to the table below for more in-
formation.
Chapter 2: Setting Up Your System 11