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question about indirect dec / indirect inc for 68000
http://easy68k.com/EASy68Kforum/viewtopic.php?f=8&t=1186
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Author:  PiCiJi [ Sun Apr 07, 2013 1:51 pm ]
Post subject:  question about indirect dec / indirect inc for 68000

An instruction which is using indirect dec / indirect inc addressing that runs in an address / bus error doesn't change the addressing register. (valid for 68000 only ... I think)

What is happening for instructions with multiple indirect dec / indirect inc addressing operations, like abcd or movem
Assume following instruction causes a bus error by reading the second operand. What value contains the register A1 afterwards?

ABCD -(A1), -(A1) -> (A1 = 2)

Author:  profkelly [ Mon Apr 08, 2013 2:25 pm ]
Post subject:  Re: question about indirect dec / indirect inc for 68000

Corrected in Sim68K v5.13.0

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