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CHAPTER 7 DETAILED EXECUTION INSTRUCTIONS
7.44
LSL (Logical Shift to the Left Direction)
Make a logical left shift of the word data in "Ri" by "Rj" bits, store the result to "Ri".
Only the lower 5 bits of "Rj", which designates the size of the shift, are valid and the
shift range is 0 to 31 bits.
■ LSL (Logical Shift to the Left Direction)
Assembler format:
LSL Rj, Ri
Ri < < Rj → Ri
Operation:
Flag change:
N: Set when the MSB of the operation result is "1", cleared when the MSB is "0".
Z: Set when the operation result is "0", cleared otherwise.
V: Unchanged
C: Holds the bit value shifted last. Cleared when the shift amount is "0".
Execution cycles:
1 cycle
Instruction format:
Example:
LSL R2, R3
138
N
Z
V
C
C
C
–
C
MSB
1
0
1
1
R2
0 0 0 0
0 0 0 8
R3
F F F F F F F F
N Z V C
CCR
0 0 0 0
Before execution
0
1
1
0
Rj
LSB
Ri
R2
0 0 0 0 0 0 0 8
R3
F F F F F F 0 0
N Z V C
CCR
1 0 0 1
After execution
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