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MICROPROCESSOR INSTRUCTION REFERENCE->ROL

ROL   Rotate Left (without Extend)

Compatibility: 68000, 68010, 68020 and CPU32 families.


Destination rotated by <count> -> Destination

C <- OPERAND <- high order bit

Assembler Syntax:ROL Dx,Dy
ROL #<data>,Dy
ROL <ea>

Dx contains shift count; Immediate shift data may be 1 - 8;
Memory can be shifted only 1 bit

Size:  Byte, Word, Long except if Memory Shift when only Word Allowed

Rotates the bits of the operand left.  The extend bit is not included in the rotation.


Condition Codes:

N    Set if most significant bit of result is set, else cleared
Z    Set if result zero, else cleared
V    Always cleared
C    Set according to last bit shifted out of operand, cleared for a shift
    count of zero
X    Not affected

    
Allowable Addressing Modes
    
ROLDx,Dy
ROL#(data),Dy
ROL(An)
ROL(An)+
ROL-(An)
ROL(d16,An)
ROL(d8,An,Xn)
ROL(bd,An,Xn) 2
ROL([bd,An,Xn],od) 1
ROL([bd,An],Xn,od) 1
ROL(xxx).W
ROL(xxx).L
1   68020 only
2   68020 and CPU32 only