Re: 7501/8501 R/W gate in

Am 30.08.20 um 18:04 schrieb Frank Wolf:
> But GATE_IN is definitely a latch enable signal and R/W# is latched. I 
> reversed it from the die
> and my conclusions were tested and proven; you certainly followed my 
> posts on F64 ;)

That's what I've figured out from the timing diagrams in the system 
manual as well some time ago.

> On 30.08.2020 17:59, Gerrit Heitsch wrote:
>> On 8/30/20 5:39 PM, Frank Wolf wrote:
>>> Hi _at_ll,
>>>
>>> almost right... R/W# can change as long as GATE_IN is high. In other 
>>> words: Francesco is right.
>>
>> Never saw it change anywhere else but on the rising edge of MUX 
>> though. The difference between what you see on the scope and what the 
>> circuit really does. :)
>>

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.