> 20 years ago, I set up an IBM AT to emulate a
printer. ?I based it on
> Bruce Eckel's Microcornucopia parrallel port interfacing articles. ?I used
On Mon, 5 Jul 2010, Liam Proven wrote:
I did that, around that time, too.
I had to get all the files off an ancient dedicated wordprocessor -
possibly a QUME or a Wang box, I forget now. It had a weird floppy
format - I don't remember the details, maybe 8", maybe hard-sectored?
No way to read 'em on a 1980s PC, anyway.
Its printer was a serial daisywheel of no known type or compatibility.
So I wrote a QuickBASIC app for a PC to receive data from the serial
port and dump it in files. I wired up a nullmodem cable, loaded each
The one that I was dealing with was "Centronics" parallel, but Eckels had
described in detail how to modify one of the common parallel ports for
bi-directional, and I wired up a cable with the opposite gender blue
ribbon connector, so that the alien machine thought that it was talking to
a printer.
In retrospect, a parallel to serial adapter would probably have been
easier.
file on the WP, then printed it. The PC asked for a
filename, captured
it, stripped out all the non-ASCII, single carriage returns and things
like that, then saved it to disk. As it was a daisywheel, there was no
formatting information worth noting; it did a backspace-and-overprint
for bold, a code for underline which I think I threw away, and that
was about it.
Most (not all) of the early daisy wheels did underline with a backspace
and an underline character.
But then I found a problem: it did bidirectional
printing. In
*software*. For every other line, it printed
[character][backspace][backspace][character][backspace][backspace]...
etc.
Howzbout: capture line to buffer, (or read from the file), and look for
the double [backspace]s ?
What was even more fun was transferring files TO a machine with no real
connectivity (a Merganthaler from hell). Box of solenoids on the
keyboard!
--
Grumpy Ol' Fred cisin at
xenosoft.com