Mitsubishi Electric Apricot XEN pentium, Руководство пользователя, Страница: 125 / 147

XEN OWNER'S HANDBOOK A/9
Inside your computer
Appendix A
We can demonstrate that 3FB is exactly the same as 1019 by:
((256x3)+(16xF)+(1xB)=768+240+11=1019
Note
A lower case h is often used at the end of a number to ensure that
you realise it is in hex format e.g. 3FBh.
A larger hex number, and one that you will come across in
the
Memory map description below, is A0000h. To see this as
a decimal number:
16x16x16x16 16x16x16 16x16 16 1
A 0 0 0 0
16x16x16x16=65536
So A0000h is 65536x10=655360.
If you have Microsoft Windows 3.1 on your computer you may
find it helpful to use the Windows Calculator. In Scientific View
the calculator allows you to enter decimal numbers and
convert them to hex, and vice versa.
Another commonly used notation is to describe numbers as
xK or xM. Where 1K=1024 and 1M=1048576
(1048576=1024x1024). In this notation 655360 (that is
A0000h) is 640K.
Memory maps
All memory, whether it is on the motherboard or an expansion
card, is accessed somewhere in the processor’s address space.
The processor’s address space can be thought of as a list of
locations, the locations are each identified by a number. The
first, or bottom, location is address 0.