RL78/G1P
CHAPTER 3 CPU ARCHITECTURE
R01UH0895EJ0100 Rev.1.00
51
Nov 29, 2019
3.4.3 Direct addressing
[Function]
Direct addressing uses immediate data in the instruction word as an operand address to directly specify the target
address.
[Operand format]
Identifier Description
!addr16
Label or 16-bit immediate data (only the space from F0000H to FFFFFH is specifiable)
ES:!addr16
Label or 16-bit immediate data (higher 4-bit addresses are specified by the ES register)
Figure 3-17. Example of !addr16
F0000H
A 16-bit address <1> in the 64 KB area from
F0000H to FFFFFH specifies the target location
(for use in access to the 2nd SFRs etc.).
MOV
!addr16, A
Instruction code
Target memory
Memory
<1>
<1>
OP-code
Low Addr.
High Addr.
FFFFFH
Figure 3-18. Example of ES:!addr16
00000H
X0000H
OP-code
Low Addr.
High Addr.
ES
The ES register <1> specifies a 64 KB area within the
overall 1 MB space as the four higher-order bits, X, of
the address range.
A 16-bit address <2> in the area from X0000H to XFFFFH
and the ES register <1> specify the target location;
this is used for access to fixed data other than
that in mirrored areas.
Area from
X0000H to
XFFFFH
ES: !addr16
Specifies a
64 KB area
Specifies the
address in memory
Instruction code
Target memory
Memory
<1>
<2>
<2>
FFFFFH