Move.2f, Move two fractional words from, Operation assembler syntax – Freescale Semiconductor StarCore SC140 User Manual
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SC140 DSP Core Reference Manual
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MOVE.2F
Move Two Fractional Words from
MOVE.2F
Memory to a Register Pair (AGU)
Description
Status and Conditions that Affect Instruction
Status and Conditions Changed by Instruction
Example
move.2f (r7),d2:d3
Operation
Assembler Syntax
(EA)
→ Da:Db
MOVE.2F (EA),Da:Db {0
≤ EA < 2
32
,L}
MOVE.2F (EA),Da:Db
Moves two signed fractional words from memory to a data register pair (Da:Db). The effective memory
address of the two words is contained in an address register with an optional offset or post-increment (EA).
Each word is written in the HP of its respective data register, sign-extended, and the LP is zero-filled. The
reverse operation (moving from a register pair to memory) is done with saturation. It is described in
MOVES.2F.
The first operand (Da) will be moved from the lower memory address (EA). The second operand (Db) will
be moved from memory address (EA + 2). In order to maintain this behavior in both big endian and little
endian modes, the core will interpret the data bus differently in each mode. See
on page 2-56, for more detail on bus and memory behavior for each mode.
The address register values used with this instruction must be a multiple of 4, long aligned.
Register Address
Bit Name
Description
MCTL[31:0]
AM3–AM0
Address modification bits when updating R0–R7. Otherwise, the
instruction is not affected by MCTL.
EMR[16]
BEM
Set if big endian mode, cleared if little endian mode.
Register Address
Bit Name
Description
Ln
L
Clears the Ln bit in the destination registers.
Register/Memory Address
Before
After
MCTL
$0000 0000
R7
$0000 0050
SIGN
EXTENSION
ZERO FILL
SIGN
EXTENSION
ZERO FILL
39
0
16
32
Da
Db
(EA) OPERAND
(EA+2) OPERAND