On Mon, Mar 14, 2011 at 4:15 PM, Dave McGuire <mcguire at neurotica.com> wrote:
?Great stuff! ?Does anyone remember the solenoid-filled boxes that sat over
the keyboard of a Selectric typewriter and turned it into a printer, that
were sold via magazine ads and such? ?This sorta reminds me of those, going
in the other direction. ?Neat!
I remember them, and since my mother was a professional typist (court
transcripts and such), we *had* more than one Selectric at home.
Unfortunately, we (I) didn't have the money as a kid to buy the
solenoid boards (and as it turns out never did buy even a used printer
until I was in college), but my mother was always interested in the
approach.
It didn't help that we had a PET, and at the time, there was an extra
expense to pick up an IEEE-488->Centronics board/box (there were
several available, ISTR). Later, when I _did_ have a tank of a dot
matrix printer (wide carriage with two heads, one for columns 1-80,
one for 81-132), I rigged up a CBM User Port-to-Centronics cable
(which I was looking at mere days ago) and wrote my own Centronics
printer driver and tapped it into the IEEE routine vectors on a C-64.
The cable would work on a PET, but not the software as designed (the
big difference being that the system call vectors are in ROM on a PET
and bump through RAM on a C-64, simplifying the task of hacking in
your own routines to replace ones in ROM). If I had a need, with what
I know now, I'm sure I could hack the code I wrote to allow a PET to
drive a parallel printer with a special set of routines called
explicitly to do a screen dump or emit a string, but to avail myself
of the convenient OPEN/PRINT#/CLOSE method that works with true IEEE
devices, custom ROMs would be required.
-ethan