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by heinrichhartman 804 days ago
What does "discrete logic" mean in this case? Why would this prevent interrupts?
1 comments

> What does "discrete logic" mean in this case?

74xx series ICs (eg. 74ACT family in case of the cpu, if I read correctly).

More generally, it may refer to "basic logic elements whose function is easily inspected".

> Why would this prevent interrupts?

Not at all - in theory.

In practice, interrupt support tends to complicate cpu designs. Complicate = more logic = more ICs. So builder decided against it & chose not to implement interrupts on the cpu.

Just to clarify: CPUs built with discrete logic can definitely have interrupts (e.g. PDP-11/45, VAX 11/780).