Motorola 24-Bit Digital Signal Processor, DSP56000 manual Address Register Indirect No Update

ADDRESSING

EXAMPLE: MOVE A1,X: (R0)

			BEFORE EXECUTION
A2			A1				A0
55	48	47	24	23		0
0	1	2 3 4 5 6 7		8	9 A B C D
7	0	23	0	23		0
						X MEMORY
				23		0

$1000 X X X X X X

150

R0 $1000

150

N0 XXXX

150

M0 $FFFF

Assembler Syntax: (Rn)

Memory Spaces: P:, X:, Y:, XY:, L:

Additional Instruction Execution Time (Clocks): 0

Additional Effective Address Words: 0

					AFTER EXECUTION
		A2			A1				A0
55		48 47		24	23		0
		0	1	2	3 4 5 6 7	8	9 A B C D
7			0 23		0	23		0
								X MEMORY
						23		0

$1000 $ 2 3 4 5 6 7

150

R0 $1000

150

N0 XXXX

150

M0 $FFFF

Figure 4-4 Address Register Indirect — No Update

modifying the contents of Rn without an associated data move.

4.4.1.4Postincrement By Offset Nn

The address of the operand is in the address register, Rn (see Table 4-1and Figure 4-7). After the operand address is used, it is incremented by the contents of the Nn register and stored in the same address register. The contents of the Nn register are unchanged. This mode can be used for making XY: memory references and for modifying the contents of

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