Daisy chain 74HC595 causes issues

I said before

but according to the 74hc595/74hct595 data sheet, if I'm reading it correctly, at 5V supply, a high input is 3.5V or over for the 74hc595. So the 3.3V signal from the esp isn't enough. But for the 74hct595, it's 2.0V or over, so no problem. This is exactly what @Paul_B said, of course. But with a 3.3V supply, 74hc595 accepts anything over around 2.3~2.5V as high, so the esp signals are ok. For 74hct595, you can't run that on 3.3V supply, the minimum is 4.5V, so you would need to run it at 5V, but that's ok, it can still accept the esp's signals.

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