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Address Register Indirect with Predecrement

Similar to the previous mode, except that the address is decremented before the data transfer.

• MOVE.L -(A0),D3 - the contents of A0 is decremented by 4, then the contents of the memory location with the new address value is copied to D3.

• MOVE.W -(A0),D3 - the contents of A0 is decremented by 2, then the contents of the memory location with the new address value is copied to D3[15:0].

These auto modes are very usefuuul for lists, tables, arrays, and stacks.

Stack operation. For stacks growing into lower memory: PUSH - predecrementing, PULL - postdecrementing.

This pushes a longword and then a word onto the stack:

MOVE.L D0,-(A7)
MOVE.W D1,-(A7)

This pulls the word item from the stack:

MOVE.W (A7)+,D3

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