dsp56800e Freescale Semiconductor, Inc, dsp56800e Datasheet - Page 542

• Manufacturer Part Number: dsp56800e
• Description: 16-bit Digital Signal Controller Core
• Manufacturer: Freescale Semiconductor, Inc

MOVE.W
Operation:
S → D
S → D
Description: Move a 16-bit value from a register to memory, from memory to a register, from one memory location
Example 1:
Explanation of Example:
A-198
Before Execution
(two parallel reads)
(no parallel move)
A2
0
to another, or from one register to another register, or load a register or a memory location with an im-
mediate value. All memory locations are specified with word pointers, offsets are specified as word
offsets, and absolute addresses are specified as word addresses.
Operands are affected as follows:
– When a 16-bit or FF2 register is a source, the entire register is loaded into the destination.
– When a 24-bit register is a source, the lower 16 bits are loaded into the destination.
– When a full accumulator is a source, the value of the FF1 portion is loaded into the destination.
– When a 16-bit or FF2 register is a destination, the entire register is filled with the source value.
– When a 24-bit register is a destination, the lower 16 bits are written and signed extended
– When a full accumulator is a destination, the FF1 portion is written with the source value and sign
– When the Y register is a destination, the Y1 portion is written and Y0 is zero filled.
– When the N register is used for post-update (for example, X:(Rn)+N), the value of N is truncated
MOVE.W
Prior to the memory move, the accumulator register A contains the value $0:6677:8888. After execu-
tion of the MOVE.W X:(R0+$20),A instruction, the FF1 portion of A is updated with the value in
memory that is pointed to by the word pointer R0, with a word offset of $20 (word location $004464).
The FF2 portion of A is sign extended, and the FF0 portion of A is zero filled. The value in the A ac-
cumulator becomes $F:9060:0000; R0 is unchanged.
appropriately. Refer to MOVEU.W for unsigned word initialization of AGU registers.
extended through bit 35; the FF0 portion is zero filled. Sign extension is also performed when the
source operand is an immediate value that is smaller than 16 bits.
to 16 bits and sign extended to 24 bits before it is added to Rn.
6677
R0
X:$4464
A1
X:(R0+$20),A
004444
DSP56800E Core Reference Manual
8888
9060
A0
Move Word
; move word from memory into A
Assembler Syntax:
MOVE.W
MOVE.W
After Execution
A2
F
S,D
S,D
R0
9060
X:$4464
A1
(two parallel reads)
(no parallel move)
Freescale Semiconductor
004444
MOVE.W
0000
9060
A0