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MICROPROCESSOR INSTRUCTION REFERENCE->NBCD

NBCD  Negate Decimal with Extend

Compatibility: 68000, 68010, 68020 and CPU32 families.


0 - Destination - X -> Destination


Assembler Syntax:   NBCD <ea>


<ea> - data alterable

Size:  Byte

Subtracts the destination operand and the extend bit from zero.  The operation is performed using binary coded decimal arithmetic.  The packed BCD result is saved in the destination location.  This instruction produces the tens complement of the destination if the extend bit is zero, or the nines complement if the extend bit is one.

Condition Codes:

N    Undefined
Z    Cleared if result non-zero, else unchanged
V    Undefined
C    Set if borrow (decimal), else cleared
X    Set same as carry bit

    
Allowable Addressing Modes
    
<ea>
    
NBCDDn
NBCD(An)
NBCD(An)+
NBCD-(An)
NBCD(d16,An)
NBCD(d8,An,Xn)
NBCD(bd,An,Xn) 2
NBCD([bd,An,Xn],od) 1
NBCD([bd,An],Xn,od) 1
NBCD(xxx).W
NBCD(xxx).L
1   68020 only
2   68020 and CPU32 only