7
DETAILS OF INSTRUCTIONS
S1C33 FAMILY C33 PE CORE MANUAL
EPSON
111
ld.ub
%rd
, [
%rb
]
Function
Unsigned byte data transfer
Standard)
rd
(
7
:
0
)
←
B[
rb
],
rd
(
31
:
8
)
←
0
Extension
1
)
rd
(
7
:
0
)
←
B[
rb
+
imm13
],
rd
(
31
:
8
)
←
0
Extension
2
)
rd
(
7
:
0
)
←
B[
rb
+
imm26
],
rd
(
31
:
8
)
←
0
Code
15
12
11
8
7
4
3
0
0
0
1
0
0
1
0
0
r b
r d
0x24__
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Flag
IE C V Z N
– – – – –
|
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Mode
Src: Register indirect
%rb
=
%r0
to
%r15
Dst: Register direct
%rd
=
%r0
to
%r15
CLK
One cycle (two cycles when
ext
is used)
Description
(
1
) Standard
ld.ub
%rd
,[
%rb
]
; memory address =
rb
The byte data in the specified memory location is transferred to the
rd
register after being zero-
extended to
32
bits. The
rb
register contains the memory address to be accessed.
(
2
) Extension
1
ext
imm13
ld.ub
%rd
,[
%rb
]
; memory address =
rb
+
imm13
The
e x t
instruction changes the addressing mode to register indirect addressing with
displacement. As a result, the content of the
rb
register with the
13
-bit immediate
imm13
added
comprises the memory address, the byte data in which is transferred to the
rd
register. The
content of the
rb
register is not altered.
(
3
) Extension
2
ext
imm13
; =
imm26
(25:13)
ext
imm13
; =
imm26
(12:0)
ld.ub
%rd
,[
%rb
]
; memory address =
rb
+
imm26
The addressing mode changes to register indirect addressing with displacement, so the content
of the
rb
register with the
26
-bit immediate
imm26
added comprises the memory address, the
byte data in which is transferred to the
rd
register. The content of the
rb
register is not altered.
