dsp56800e Freescale Semiconductor, Inc, dsp56800e Datasheet - Page 88

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

Data Types and Addressing Modes
3.6.4
The immediate address modes do not use an address register to specify an effective address. These modes
specify the value of the operand directly in a field of the instruction.
3.6.4.1
The 4-bit immediate data operand is located in the instruction operation word. In the ADDA instruction,
the 4-bit unsigned value is zero extended to form a 24-bit value. In data ALU shifting instructions, the 4-bit
value is zero extended to form a data ALU operand.
3.6.4.2
The 5-bit immediate data operand is located in the instruction operation word. When the MOVE.L
instruction is used to write an accumulator, the 5-bit value is sign extended to form a 36-bit value. In data
ALU instructions, the 5-bit value is zero extended to form a data ALU operand.
Figure 3-24 demonstrates this addressing mode.
3.6.4.3
The 6-bit immediate data operand is located in the instruction operation word. The 6-bit unsigned value is
zero extended to form a 16-bit loop count. It is used by the DO and REP instructions when the loop count
is specified with an immediate value.
3-38
Available for: Long
Assembler Syntax: #xx
Additional Instruction Execution Cycles: 0
Additional Effective Address Program Words: 0
B
Immediate Address Modes
35 32 31
B2
X
4-Bit Immediate Data: #x
5-Bit Immediate Data: #xx
Figure 3-24. Immediate Addressing: 5-Bit Immediate Data to Accumulator
6-Bit Immediate Data: #xx
X
5-Bit Immediate into Full 36-Bit Accumulator Example:
Before Execution
X
B1
X
X
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DSP56800E Core Reference Manual
X
X
B0
X
X
0
B
35 32 31
B2
F
F
F
After Execution
B1
MOVE.L #-4,B
F
F
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Freescale Semiconductor
F
F
B0
F
C
0