7.125 EXTSB (Sign Extend from Byte Data to Word Data)
Extend the byte data indicated by "Ri" to word data as a signed binary value.
■ EXTSB (Sign Extend from Byte Data to Word Data)
Assembler format:
EXTSB Ri
Operation:
exts (Ri) → Ri (byte → word)
Flag change:
N, Z, V, and C: Unchanged
Execution cycles:
1 cycle
Instruction format:
Example:
EXTSB R1
N
Z
V
C
–
–
–
–
MSB
1
0
0
1
R1
0 0 0 0 0 0 A B
Before execution
CHAPTER 7 DETAILED EXECUTION INSTRUCTIONS
0
1
1
1
1
0
LSB
0
0
Ri
R1
F F F F F F A B
After execution
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