@Kai,

why you not read your own link before you vote wrong :-(

"The higher threshold level of the HC or AC CMOS logic increases the noise immunity by approximately 1.5 volts. This is generally all that is needed to prevent the undesired latching by ALE."

Exactly what I already said !!!

And if you need maximum speed (XTAL = 33MHz), the AC CMOS must be used to avoid to big delay of the memory access time, especially on code memory access.


Peter