Hello David,
 >>  Why is it not just as important to CLI and STI when saving the 
gisters?
 DK> Because _saving_ them does not _change_ them.
 DK> But when it comes time to actually _change_ where your stack pointer is 
 DK> aiming at...
 DK> You wouldn't want some other process to come in and try to use the stack
 DK> just at the instant when you'd changed the SP but not the SS, would you?
     I was thinking about reading and writing to memory/registers.
     If an interrupt occurs, the operation is just delayed.
     With a stack and it's pointer, a change must be completely controlled.
     Ok, thanks, David.
Kind regards, Barry 
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