This wasn't a large IBM lineprinter and I'm pretty sure it was 1" tape, but
it may well have been inspired by those machines. It would likely have
been used with custom fanfold paper for invoices, cheques etc. - certainly
the same sort of customer-specific those machines dealt with, but for the
small office. A predecessor to the PC.
On Thu, Jun 8, 2023 at 7:13 PM Paul Koning <paulkoning(a)comcast.net> wrote:
On Jun 8, 2023, at 1:18 PM, Adrian Godwin
<artgodwin(a)gmail.com> wrote:
...
I've seen mylar tape used in a tiny loop where it controlled the
movements of a printer platen. I don't recall now whether it was used for
horizontal or vertical space - my recollection was the latter but it was a
long time ago.
I don't know why it wasn't controlled by ASCII - a good bit of the
character set is dedicated to print head control. I think a different tape
had to be installed to match the program that was being run. The machine
was used for accountancy in about 1975, It was a bit like a large LA120
(but included the calculating part) and made by the french Logabax company.
Many line printers used a "VFD" tape (vertical format definition?) which
is a 12-channel tape with one row per line on the paper. The idea was that
you could tell the printer "skip to channel N" and it would advance the
paper until a hole in that channel was seen. By convention, channel 1
marks the top of the page, and in fact typically that position was punched
all the way across so a skip to an "unused" channel would not produce
runaway paper. Channels other than 1 would be used for custom forms, where
it would save time to skip across part of the form rather than advancing
line by line to the desired spot.
If you only ever used regular size paper this stuff wouldn't be obvious,
but an operator who had to handle other forms, like checks or label stock
or anything else that wasn't just plain 60/66 line pages, would have to
change the paper along with the matching format tape. Some printers had
small local memories that could be downloaded with the form definition tape
data, avoiding the need for the operator to switch the tape manually.
paul