On 2015-12-15 1:54 AM, Paul Birkel wrote:
Looks very nice! Is there documentation for it somewhere? I also have
a Selectric (unfortunately it's located distant from me at the moment
so I can't provide particulars) that I worked on interfacing to a
micro in the mid-70's. I was using a MC6800 in my recollection, but I
don't believe that I ever achieved operational status. Presumably I
was working from an article in one of the hobbyist magazines of the
era. I would have guessed Byte, but that doesn't seem to be the case
based on recent search. Any hints from folks on what magazine/article
that might have been? The Selectric wasn't one of the curvy(ier)
office models; I recall it being a rather boxy affair with plenty of
right-angles on the housing and a medium shade of blue -- presumably
"IBM Blue". Rather utilitarian in design. Even *more* utilitarian than
this one:
http://www.covingtoninnovations.com/selectric/100112-Selectric-in-situ.jpg
It included a full keyboard. I'm not sure anymore whether it operated
in local-mode or was set up as two separate devices and therefore
needed to be connected up to a remote controller to get local copy. It
might have been a rehoused Selectric mechanism in a third-party
enclosure and the IBM-like color a red herring. My recollection is
that it was longer front-to-back; presumably the rearward extension
housed the additional electronics. I have absolutely no idea how I
acquired it. No luck finding a matching photo online as yet. I believe
that the Selectric came configured for remote operation, but
presumably using an EBCDIC-based data stream. I vaguely recall a DB-50
connector, but it's been an awfully long time ... Does this
description sound familiar to anyone? ----- paul
The selectric pictured in your link above is a standard Office Products
(OP) Selectric II. Some of the selectric terminals where in a enclosure
that was very similar. The 2741, 2741 and 1980 I/O units where in a
similar case but where sunk into a cutout in the desk they where mounted
in. The 2970 mod 8 and mod 11 banking terminals where in larger boxy
enclosures to accommodate extra hardware that was hung on them for
banking applications. The 3735 programmable terminal had a Selectric
I/O II attached that looked just like an OP Selectric except for some
indicator lights and the big cable exiting out the back. None of the
Selectric terminals I worked on had any electronics inside, except arc
suppression diodes, all of the electronics where housed in an attached
control unit.
The selectric terminals I worked on where mostly used for banking teller
station and finance company terminals. The coding of the data was more
geared towards the position of the characters on the type ball with 4
bits for rotate (+1, +1, +2, and -5) and two bits for tilt (+1 and +2)
and there where also code points allocated to function such as tab, CR +
LF, space, shift up and shift down. The relation of the code point to
the graphic printed depended on the layout of the type ball being used,
and they where not always the same as the OP selectric. The type ball
used by the banks for instance, was laid out so that no two numbers
where adjacent to each other on the type ball to lessen the risk of
printing an incorrect number.
Paul.
