18 Jan
2003
18 Jan
'03
3:22 a.m.
On Fri, 17 Jan 2003, Tony Duell wrote:
The System 23 I briefly worked on (as in 'got
inside') had a DE9
connector for the printer IIRC. It was a _current loop_ serial port, and
of course the character set is EBCDIC (but as you say, that's a minor
problem).
I was wondering what that connector was. Now I know :)
I think (based on the current loop on the PC Async
card) that IBM's
convention was that transmiters were active and non-isolated, receivers
were passive and opto-isolated, but do check this before hooking
anything up.
Cool, after the punch card project I actually know what you're talking
about ;)
Sellam Ismail Vintage Computer Festival
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