Category:8086 Assembly: Difference between revisions
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==Architecture Overview==
===Segmented Memory===
The 8086 uses a segmented memory model, similar to the Super Nintendo Entertainment System. Unlike banked memory models used in the Commodore 64 and late NES games, segment addresses are held in <i>segment registers</i>. These segment registers are 16 bit and get left-shifted by 4 and added to the pointer register of interest to determine the memory address to look up. The 8086 has four in total, but only the
<lang asm>;This is NOT valid code!
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mov ax, @data ;I chose AX but I could have used BX, CX, or DX.
mov ds, ax ;load DS with the data segment.</lang>
It's important to remember the subtle distinction between a ''segment'' and a ''segment register.'' Your program might have labeled ''segments'' such as <code>.data</code> and <code>.code</code>, but in order to properly read from/write to these sections you'll need to load their memory locations into ''segment registers.''
===Data Registers===
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