Fujitsu CM71-00101-5E User Manual
164
CHAPTER 7 DETAILED EXECUTION INSTRUCTIONS
7.68
LDUB (Load Byte Data in Memory to Register)
Extends with zeros the byte data at memory address "(R14 + o8)", loads to "Ri".
The value "o8" is a signed calculation.
The value "o8" is a signed calculation.
■
LDUB (Load Byte Data in Memory to Register)
Assembler format:
LDUB @ (R14, disp8), Ri
Operation:
extu ((R14 + o8))
→
Ri
Flag change:
N, Z, V, and C: Unchanged
Execution cycles:
b cycle(s)
Instruction format:
Example:
LDUB @(R14, 1), R3
N
Z
V
C
–
–
–
–
MSB
LSB
0
1
1
0
Ri
o8
12345678
x x x x
x x x x
R3
R3
2 1
0 0 0 0
0 0 2 1
12345678
12345679
12345679
2 1
1 2 3 4 5 6 7 8
R14
1 2 3 4
5 6 7 8
R14
Instruction bit pattern :
0110 0000 0001 0011
Memory
Memory
Before execution
After execution