dsp56000 Freescale Semiconductor, Inc, dsp56000 Datasheet - Page 63

• Manufacturer Part Number: dsp56000
• Description: 24-bit Digital Signal Processor Family Manual
• Manufacturer: Freescale Semiconductor, Inc

an extra instruction cycle, cannot be used for making XY: memory references.
4.4.1.7
The address of the operand is the contents of the address register, Rn, decremented by
1 before the operand address is used (see Table 4-1 and Figure 4-10). The contents of
Rn are decremented and stored in the same address register. This addressing mode re-
quires an extra instruction cycle. This mode cannot be used for making XY: memory
references, nor can it be used for modifying the contents of Rn without an associated data
MOTOROLA
EXAMPLE: MOVE X1,X: (R2)+N2
Assembler Syntax: (Rn)+Nn
Memory Spaces: P:, X:, Y:, XY:, L:
Additional Instruction Execution Time (Clocks): 0
Additional Effective Address Words: 0
47
23
A
Figure 4-7 Address Register Indirect — Postincrement by Offset Nn
5
Predecrement By 1
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BEFORE EXECUTION
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M2
R2
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X MEMORY
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ADDRESS GENERATION UNIT
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ADDRESSING
47
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A
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AFTER EXECUTION
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