Re: RS-232 port genders

[datajerk <datajerk@gmail.com>]

On Jun 21, 9:47 am, datajerk <dataj...@gmail.com> wrote:
> I worked with a lot of RS-232 devices in the mid '80s to the early
> '90s.  Dumb terminals, modems, printers, Alpha Micros, the Apple II,
> short-hall modems, data collection devices, many different RS-232
> multiplexers to add terminals to various UNIX systems, etc...
> Excluding a few oddballs (e.g. Macs) they all used female DB25
> connectors except, IIRC, IBM PCs (and later the multiplexers started
> to use RJ45s).  The PCs used a female DB25 for the parallel port and a
> male DB25 for the serial port.  I always thought this was a poor
> decision since repairing broken pins on a cable was cheaper than a
> device.
>
> As I dug through my vintage serial devices I found a 1985 HP-IL to
> RS232C device used to provide a serial port to HP-IL devices such as
> the HP41 calculator.  It also has a male serial port.  That has left
> me with the thought that something greater was redefining the
> convention or was it simply the PC that started the trend to use male
> RS-232 ports primarily on computers?
>
> In any case, what got me thinking about this was the installation of a
> newly acquired SSC card for my IIe.  Given my history I was neither
> shocked or surprised, but it got me thinking.
>
> I plan to build my own cable for the SSC with a male DB25 to conform
> with convention and to distinguish it from the female DB25 port I plan
> to install for my printer card.  Perhaps that was IBM's thinking as
> well.

I failed to mention that the SSC came with a female DB25.