Hot swap connector interface (hot plug, live insertion)

I'd recommend against hot-plugging anything into a printer port - in days of yore, you could swap out a printer adapter for about $5.00; these days, you blow out the mother board (at least the printer port part).

Otherwise, then I'd use not only longer ground pins, but longer power pins, i.e. 3 lengths ground the longest, power mid-size, then signals.

Or, better yet, design your circuit robustly enough to handle anything/everything that can go wrong.

Good Luck! Rich

Well, it isn't possible without a connector. What constitutes 'specialized' is often a matter of don't-plug-the-wrong-thing-in-here.

Some logic (MC1489A receiver and MC1488 transmitter) is designed for noisy transient-filled signal wiring, and speed usually suffers when you use that kind of interface.

Use of a coupling transformer (which can insulate and limit power transfer by saturating) can allow high speed and good rejection of static and transients, but requires modulation and demodulation. That's how Ethernet 10baseT/100baseT/1000baseT works. Usually you lose DC sensitivity; it was possible to add DC power to Ethernet, but it wasn't easy.

The reason your printer-connect example works is the third-prong power pin, which grounds both the printer and computer to your wall socket before any data connectors are mated. SCSI is similarly usually capable of hot-plugging.

Of koarse it is posyball and sympal! Circuitry would sense the connection and then do sequential powering.

...everything? Earthquakes? Tornadoes? Flowing lava? Floods? etc?

Thanks for all the feedback. Very insightful.