7
DETAILS OF INSTRUCTIONS
120
EPSON
S1C33 FAMILY C33 PE CORE MANUAL
ld.w
%rd
, [
%rb
]
Function
Word data transfer
Standard)
rd
←
W[
rb
]
Extension
1
)
rd
←
W[
rb
+
imm13
]
Extension
2
)
rd
←
W[
rb
+
imm26
]
Code
15
12
11
8
7
4
3
0
0
0
1
1
0
0
0
0
r b
r d
0x30__
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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.w
%rd
,[
%rb
]
; memory address =
rb
The word data in the specified memory location is transferred to the
rd
register. The
rb
register
contains the memory address to be accessed.
(
2
) Extension
1
ext
imm13
ld.w
%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 word 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.w
%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
word data in which is transferred to the
rd
register. The content of the
rb
register is not altered.
Caution
The
rb
register and the displacement must specify a word boundary address (two least significant
bits =
0
). Specifying other addresses causes an address misaligned exception.
