Re: 7501/8501 R/W gate in

 > Of course you see it changing at the rising edge - that's when the 
latch goes to transparent mode again. ;-)
 > Even if the core changes R/W before (what it does IMHO) you won't see 
it on the R/W pin outside because it's "masked" by the latch.

Exactly.

 > You can tie GateIN to HIGH and then see what the core really does.
 > As I said, I have scope screenshots. You can see there when AEC 
tristates R/W and when TED takes over and drives R/W to HIGH. This is 
not visible when GateIN is connected to MUX.

Don't we all have some scope shots of the 8501? LOL
You don't see what the GATE_IN logic is doing when it's low... and it's 
doing more than just latching R/W#

Cheers,

Frank