With few exceptions, it makes little or no difference.
One exception is where several drivers can yank on a wire-OR signal, like an
interrupt line. Then active-low may be preferred for CMOS because available
open-drain outputs generally pull down; I don't know if there is a modern
technological preference for this. Maybe it's inherited from TTL where the
pulldown transistor was stronger. For ECL one would prefer active-high,
because NPN emitter followers only pull the output high.
Another case is where a bus uses terminators, pull-up, or pull-down
resistors, and is in one state more often than the other. If there are
pull-ups and 0's are more prevalent than 1's, you can save some power if
it's active low.
Long lines broken up with buffers, should have both active-low and
active-high sections, inverting once at each repeater. Otherwise asymmetry
would accumulate.
Regards,
Andy
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