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Offline Piru

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Re: more 68K questions
« on: April 24, 2006, 09:44:09 AM »
http://www.freescale.com/files/archives/doc/ref_manual/M68000PRM.pdf

In addition there are some other limitations to 68000 barring the instruction set:

- The easiest way to crash 68000 is to access word or longword data from odd address.

example:
Code: [Select]

  lea    data(pc),a0
  move.w 1(a0),d0
  rts

  even
data:
  dc.b   1,2,3

- Another easy way to mess up is to use *2, *4, or *8 index on instructions (multiplier is simply ignored by 68000).

example:
Code: [Select]

  move.l 0(a0,d0.w*2),d0
  rts