Assembly Language Help (alang.hlp) (
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Topic list)
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XCHG Instruction
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────────────────────────────────────────────────────────────────────────────
1000011w mod,reg,r/m disp (0, 1, or 2)
─────────────────────┬─────────────────────┬────────────────────────────────
XCHG reg,reg │ xchg cx,dx │ 88/86 4
│ xchg dl,dh │ 286 3
│ xchg al,ah │ 386 3
│ │ 486 3
─────────────────────┼─────────────────────┼────────────────────────────────
XCHG reg,mem │ xchg [bx],ax │ 88/86 17+EA (W88=25+EA)
XCHG mem,reg │ xchg bx,pointer │ 286 5
│ │ 386 5
│ │ 486 5
─────────────────────┴─────────────────────┴────────────────────────────────
10010reg
─────────────────────┬─────────────────────┬────────────────────────────────
XCHG accum,reg16* │ xchg ax,cx │ 88/86 3
XCHG reg16,accum* │ xchg cx,ax │ 286 3
│ │ 386 3
│ │ 486 3
─────────────────────┴─────────────────────┴────────────────────────────────
* On the 80386/486, the accumulator may also be exchanged with a
32-bit register.
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