Re: [hatari-devel] Strange behaviour with ROL.B ?

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Le 28/06/2020 à 10:04, Laurent a écrit :
Hi everybody,


I encounter a situation I can't explain for now with ROL.B and the Carry flag in the 68030 state register.

My example program :

Clear d7

Set d0 to 9

rol.b d0 2 times with values $10 and $40 and check the C flag of the state register after each rol.
rol.b d0 by $10   (if carry bit is set, add 1 to d7)

rol.b d0 by $40   (if carry bit is set, add 2 to d7)

Then I display the value of d7 on screen (0, 1, 2 or 3) depending of the state of the Carry bit.

When I run the program, I can read on screen  "3"; which means that the carry bit was "1" for the 2 rol instructions.
When I trace the program under hatari debugger (which is supposed to be 
Hi

do you mean you see a difference between a real falcon and Hatari in 68030 mode ?



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