4 Sep
2002
4 Sep
'02
12:38 p.m.
On Wed, 4 Sep 2002, Tony Duell wrote:
I always thought that was called RS-422.
The Macintosh standard serial port was a RS-422 serial port. When I went
to look up what that meant, the only difference I could find was the
voltage levels.
RS-422: 0v to 5v
RS-232: -5v to 5v
The documentation I found went on to say that RS-422 was backaward
compatiable with RS-232.
--
tim lindner tlindner(a)ix.netcom.com
However, the original question mentioned RS232.
Which is _not_ the same
as serial. RS232 implies certain voltage levels.
The CBM and Atari drives do not use an RS232 interface.
AND,..
If I recall correctly, the Tandy Pdd1, although it was "almost
RS-232" used TTL, NOT RS-232 voltage levels. There were some trivial
adapters available to permit it to work with "real" RS-232 signals.