XT-IDE 74F573 latch recommended?

[mcs_5]

On the XT-IDE BOM, the latches are listed as 74F573, but the board shows 74LS573. An F latch is a lot faster - does it provide extra safety margin timing wise?

I went with 74HCT573 latches so far - I had those...

I got this far - now I have to order parts



I assume the DDR gates will provide me with twice the speed?

 

[Chuck(G)]

I doubt that it makes much difference in most cases. IIRC, the original XT-IDE used LS373 latches.

I've wondered myself if the XT-IDE could be re-done using a 74LS646 bus register. Probably--but with no real savings in components. Really, the answer is in programmable logic (CPLD), but sources for 5V units have pretty much dried up.

 

[glitch]

I doubt that it makes much difference in most cases. IIRC, the original XT-IDE used LS373 latches.

Indeed, it can be LS or HCT family. I was using 74F573s for a while since they were significantly cheaper from one of my usual suppliers (they had several hundred in stock).

I've wondered myself if the XT-IDE could be re-done using a 74LS646 bus register. Probably--but with no real savings in components. Really, the answer is in programmable logic (CPLD), but sources for 5V units have pretty much dried up.

Yeah, level shifting to a 3.3V CPLD is the "real answer" for getting away from discrete TTL, but it'd significantly reduce the hobbyist-friendly nature. I don't know if it'd really be any cheaper parts-wise, with the proper level shifters.