20 Jun
2013
20 Jun
'13
12:21 p.m.
I saw an IBM Quietwriter destroyed by having RS-232
fronm an old XT
Yes, but the RS232 port didn't mind to omuch...
stuffed in its centronics port. The printer port
failed in an XT so some
one put a gender changed in and plugged it into the serial port which on
an XT is on a standard 25-pin socket....
Somewhere I ahve a device for sending data down the mains cable. This
thing has a DB25 plug o nthe end, with RS232 signals o nthe 'normal PC
subset' f othe pins. The remaining pins carry TTL elve Cnetroncis
signals. There was a set of 3 adapters, a pnull-modem wiring only
the RS232 pines, a plug-to-socket DB25 adapter to move the Centroincs
pins on to the correct ones for a PC prallel port and a DB25 socket to 36
pin microribbon to conenct it to a Centroinds printer. But conenct it ot
a full RS232 port with no adapter and the magic smoke tended to escape.
And then there's the HP150. HP used DB25 _sockets_ (wired as DTEs [1])
fro the serial ports. SO when they sold an add-on board with a parallel
port on it, they used a DB25 plug for that But the board had clearly been
designed for a socket, wit hthe normal IBM PC paralell port pinouyt. The
result was that the signals were mirror-reversed. Strobe/ was on pin 13.
D0 was on pin 12. And so on.
[1] Is this what is meant by a 'serial sex offender'?
-tony