Slajd27

i	i	i	r	r	m	m	m

i i i	r r	mmm	This 16-bit field is present
000 = special	o o ii > X	000= AX	only if the instruction is a jump instruction or an operand
001 = or	01 = BX	0 0 1 = BX	isa memory addressing modę
010= and	O l Q	01 o = cx	of the form [bx+xxxx], [xxxxx].
011 - cmp	11 - DX	0 1 1 - DX	ora constant.
100    - sub 101    -add 110 = mov reg, mem/reg/const		1 0 0 - [BX] 10 1- [xxxx+BX] 110= [xxxx]
111= mov mem.	reg	111 = constant

Figurę 3.19 Basic x86 Instruction Encoding.

0 1 0	^0 1 ^1	i | m	m 1 m
i i 00    = zero operand instructions 01    = jump instructions 10    = not 11    = illegal (reserved)				mmm (if ii = 10) 000- AX 001 = BX 010= CX 011 = DX 100= [BX] 101 = [xxxx+BX] 110- [xxxx] 111 - constant	This 1 6-bit field is present only if the instruction is a jump instruction or an operand isa memory addressing modę of the form [bx+xxxx], [xxxxx], ora constant

Figurę 3.20 Single Operand Instruction Encodings