Fujitsu CM71-00101-5E User Manual
162
CHAPTER 7 DETAILED EXECUTION INSTRUCTIONS
7.66
LDUB (Load Byte Data in Memory to Register)
Extends with zeros the byte data at memory address "Rj", loads to "Ri".
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LDUB (Load Byte Data in Memory to Register)
Assembler format:
LDUB @Rj, Ri
Operation:
extu ((Rj))
→
Ri
Flag change:
N, Z, V, and C: Unchanged
Execution cycles:
b cycle(s)
Instruction format:
Example:
LDUB @R2, R3
N
Z
V
C
–
–
–
–
MSB
LSB
0
0
0
0
0
1
1
0
Rj
Ri
R2
12345678
1 2 3 4
5 6 7 8
x x x x
x x x x
R2
R3
R3
2 1
0 0 0 0
0 0 2 1
1 2 3 4
5 6 7 8
12345678
2 1
Memory
Memory
Before execution
After execution
Instruction bit pattern : 0000 0110 0010 0011