Fujitsu CM71-00101-5E User Manual

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CHAPTER 7  DETAILED EXECUTION INSTRUCTIONS
7.67
LDUB (Load Byte Data in Memory to Register)
Extends with zeros the byte data at memory address "(R13 + Rj)", loads to "Ri".
LDUB (Load Byte Data in Memory to Register)
Assembler format:
LDUB @ (R13, Rj), Ri
Operation:
extu ((R13 + Rj)) 
 Ri
Flag change:    
N, Z, V, and C: Unchanged
Execution cycles:  
b cycle(s)
Instruction format:  
Example:
LDUB @(R13, R2), R3
N
Z
V
C
MSB
LSB
0
0
0
0
0
0
1
0
Rj
Ri
R2
 
12345678
 
 
 
0 0 0 0
0 0 0 4
x x x x
x x x x
R2
R3
R3
 
 
 
 
2 1
 
 
 
0 0 0 0
0 0 2 1
0 0 0 0
0 0 0 4
12345678
1234567C
1234567C
 
 
 
 
2 1
1 2 3 4
5 6 7 8
R13
R13
1 2 3 4
5 6 7 8
Memory
Memory
Before execution
After execution
Instruction bit pattern : 0000 0010 0010 0011