Assembly Language Help (alang.hlp) (Table of Contents; Topic list)
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DEC Instruction
 Summary Key Example                    Up Contents Index Back
────────────────────────────────────────────────────────────────────────────
 
 1111111w    mod,001,r/m      disp (0, 1, or 2)
──────────────────┬─────────────────────────┬───────────────────────────────
 DEC  reg8        │ dec   cl                │ 88/86 3
                  │                         │   286 2
                  │                         │   386 2
                  │                         │   486 1
──────────────────┼─────────────────────────┼───────────────────────────────
 DEC  mem         │ dec   counter           │ 88/86 15+EA (W88=23+EA)
                  │                         │   286 7
                  │                         │   386 6
                  │                         │   486 3
──────────────────┴─────────────────────────┴───────────────────────────────
 
 01001reg
──────────────────┬─────────────────────────┬───────────────────────────────
 DEC  reg16       │ dec   ax                │ 88/86 3
 DEC  reg32*      │                         │   286 2
                  │                         │   386 2
                  │                         │   486 1
──────────────────┴─────────────────────────┴───────────────────────────────
  * 80386/486 only.
                                    -♦-