UPD78F0138 NEC, UPD78F0138 Datasheet - Page 88

• Manufacturer Part Number: UPD78F0138
• Description: (UPD78xxxx) 8-Bit Single-Chip Microcontrollers
• Manufacturer: NEC

3.4.8 Based indexed addressing
88
[Function]
[Operand format]
[Description example]
[Illustration]
The B or C register contents specified in an instruction word are added to the contents of the base register, that
is, the HL register pair in the register bank specified by the register bank select flag (RBS0 and RBS1), and the
sum is used to address the memory. Addition is performed by expanding the B or C register contents as a
positive number to 16 bits. A carry from the 16th bit is ignored. This addressing can be carried out for all the
memory spaces.
In the case of MOV A, [HL + B] (selecting B register)
The contents of the memory
addressed are transferred.
HL
Identifier
A
−
16
7
[HL + B], [HL + C]
Operation code
CHAPTER 3 CPU ARCHITECTURE
H
User’s Manual U16228EJ2V0UD
8
0
1
+
7
7
7
Description
0
1
0
1
Memory
L
B
0
1
1
0
0
0