![Epson S1C17 Series Manual Download Page 126](http://html.mh-extra.com/html/epson/s1c17-series/s1c17-series_manual_107781126.webp)
S1C17 CORE MANUAL
Seiko Epson Corporation
7-67
(Rev. 1.2)
ld.a %rd, [%rb]
Function
32-bit data transfer
Standard)
rd
(23:0)
←
A[
rb
](23:0), ignored
←
A[
rb
](31:24)
Extension 1)
rd
(23:0)
←
A[
rb
+
imm13
](23:0), ignored
←
A[
rb
+
imm13
](31:24)
Extension 2)
rd
(23:0)
←
A[
rb
+
imm24
](23:0), ignored
←
A[
rb
+
imm24
](31:24)
Code
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
0 0 1 0 0 0
r d
0 0 1 1
r b
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Flag
IL IE C V Z N
– – – – – –
|
|
|
| |
Mode
Src: Register indirect
%rb
=
%r0
to
%r7
Dst: Register direct
%rd
=
%r0
to
%r7
CLK
One cycle (two cycles when the
ext
instruction is used)
Description
(1) Standard
ld.a %rd,[%rb]
; memory address = rb
The 32-bit data (the eight high-order bits are ignored) 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.a %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 32-bit data (the eight high-order bits are ignored) in which
is transferred to the
rd
register. The content of the
rb
register is not altered.
(3) Extension 2
ext imm11
;
imm11(10:0) = imm24(23:13)
ext imm13
; = imm24(12:0)
ld.a %rd,[%rb]
; memory address = rb + imm24
The addressing mode changes to register indirect addressing with displacement, so the content
of the
rb
register with the 24-bit immediate
imm24
added comprises the memory address, the
32-bit data (the eight high-order bits are ignored) in which is transferred to the
rd
register. The
content of the
rb
register is not altered.
(4) Delayed slot instruction
This instruction may be executed as a delayed slot instruction by writing it directly after
a branch instruction with the “d” bit. In this case, extension of the immediate by the
ext
instruction cannot be performed.
Caution
The
rb
register and the displacement must specify a 32-bit boundary address (two least significant
bits = 0). Specifying other address causes an address misaligned interrupt. Note, however, that the
data transfer is performed by setting the two least significant bits of the address to 0.