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raverbashing 5 days ago

The thing I don't get about this is why did people think it was a good idea to have a serial connection over DB-25? You honestly need only 3 wires. Not 25

For a Parallel port, sure 25 wires is right there. But not for a serial port

kps 5 days ago | parent [-]

CTS, DCD, DSR, DTR, GND, PG, RI, RTR, RTS, RxD, TxD (alphabetically) makes around 11, I think.

chillingeffect 5 days ago | parent | next [-]

Plus the differential versions of most of those signals for long distance doubles the number of pins. And they have optional synchronous clocks. I did some WAN work for 3Com back in the day... :)

cestith 14 hours ago | parent [-]

A few devices back in the day could be powered over DB-25 connections besides the communications, even. Some in factories might still be.

II2II 5 days ago | parent | prev | next [-]

If I recall correctly, the DB-25 RS-232 cables also facilitated two serial connections.

kps 5 days ago | parent [-]

You do. (I've never seen that used, though.)

raverbashing 5 days ago | parent | prev [-]

Yes and then we came up with soft flow control for the win