I want to add another port to the 8051 and I plan to do so by connecting port 2 (pins 21 - 28 of the 8051) to the Q inputs (pins 2 - 9) of an edge-triggered latch (74HC574).

I will also connect the clock input to another GPIO pin of the same micro.

If I never use a movx instruction or use any instruction that modifies the behavior of the ALE line of the 8051, can I connect the latch's enable pin directly to ALE instead of ground and use ALE as if it is ground?

I'm asking because its much easier in terms of routing on a single-sided PCB. My other option would be to drill 2 extra holes and add a jumper so the enable pin would be tied to ground.


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