dsp56800e Freescale Semiconductor, Inc, dsp56800e Datasheet - Page 87

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

3.6.3.9
This addressing mode contains the 24-bit immediate displacement in 2 of the 3 instruction words. The
24-bit displacement is treated as a signed, two’s-complement value. This addressing mode is available for
move instructions. When a long-word (32-bit) memory location is accessed, the 24-bit displacement is left
shifted 1 bit before the addition. When a byte is accessed, the displacement value is given in bytes.
Figure 3-23 demonstrates this addressing mode.
Freescale Semiconductor
Available for: Byte (Byte and Word Pointer), Word, Long
Assembler Syntax: X:(Rn+xxxxxx), X:(N+xxxxxx), X:(SP+xxxxxx)
Additional Instruction Execution Cycles: 2
Additional Effective Address Program Words: 2
A
35 32 31
A2
Index by 24-Bit Displacement: (Rn+xxxxxx)
Indexed by 24-Bit Long Displacement Example:
$40800F
$007000
F
Figure 3-23. Address Register Indirect: Indexed by 24-Bit Displacement
R2
E
15
23
Before Execution
D
X
X
A1
X Memory
$007000
C
X
X
B
16 15
X
X
from the Instruction Word
24-Bit Immediate Value
Data Types and Addressing Modes
X
X
A
0
0
9
A0
+
8
7
0
A
MOVE.W A1,X:(R2+$40100F)
35 32 31
A2
$40800F
$007000
F
R2
E
15
23
After Execution
D
E
X
A1
X Memory
$007000
C
D
X
B
16 15
C
X
B
X
A
0
0
Addressing Modes
9
A0
8
7
0
3-37