memory content

From: charleswong (charles_at_syshk.com)
Date: 04/23/04 

Date: Fri, 23 Apr 2004 14:55:41 +0800

Hi,

I'm using a mmap function to display to contents of physical memory:
B000:0000 and A000:0000. The contents of these memory are all FF. What does
FF mean?

In addition, I want to make use of these memory areas because they are not
used by OS. Hence I tried to write data (e.g. 0) to these memory area. But
the memory contents were not changed. They still showed FF. Are these memory
areas protected (by OS?) (by Linux?)?

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