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Old 20 August 2018, 18:04   #52
meynaf
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Join Date: Nov 2007
Location: Lyon / France
Age: 46
Posts: 3,603
Quote:
Originally Posted by ross View Post
ipl=6 doesn't allow any maskable IRQ (same as 7)
ipl=0 allows >0, so every IRQ
ipl=1 allows >1, and so on
In my memory it did put level+1 in ipl field when an interrupt occurs. I guess it's been too long i haven't fiddled with these...

But then ipl=7 would mask level 7 but they just prevented it ?


Quote:
Originally Posted by ross View Post
Well, I can understand for the listed instructions, that are all with modification of the destination, but not for a read only operation!
(if same die part is used for this operation is sure a bad implementation, but ehi, is a 1979 project with limited transistor usable )

I must always remember not to use it

The CLR bug is a strong hint in that direction anyway. Damned electronicians always take shortcuts where they shouldn't

Another reason for me to prefer coding on 68030
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