Epson 4SLC2-50 - Manual (Page 48)

Using Memory
Your computer comes with 4MB or 8MB of memory, and you may
have installed an optional expansion memory module to increase
the total amount. This section describes how the memory in your
computer works. Also be sure to see your MS-DOS manual for
complete information on memory management.
A computer’s memory is divided into three types: conventional,
reserved, and extended. The following diagram shows the
relationships between these types of memory and their addresses.
All memory in a computer is managed using addresses—numbers
that describe the location of each byte of data. Each memory chip
must have its own set of unique addresses so that the operating
system knows where to store and find data.
Conventional memoy is memory that MS-DOS recognizes and
manages directly. The size of conventional memory is limited to
640KB and has addresses in the range 0 to 640KB.
Reserved memory is memory in the range 640KB to lMB. The
system enhances its performance by using 128KB of this memory
as shadow RAM, and the remaining memory is available.
2-16 Using Your Computer