[TUHS] Blit source

Norman Wilson norman at oclsc.org
Thu Dec 19 10:16:56 AEST 2019

I sense a hint of confusion in some of the messages
here.  To lay that to rest if necessary (and maybe
others are interested in the history anyway):

As I understand it, the Blit was the original terminal,
hardware done by Bart Locanthi (et al?), software by
Rob Pike (et al?).  It used an MC68000 CPU.  Western
Electric made a small production run of these terminals
for use within AT&T.  I don't think it was sold to the
general public.

By the time I arrived at Bell Labs in late 1984, the
Standard Terminal of 1127 was the AT&T 5620, locally
called the Jerq.  This was a makeover with hardware
redesigned by a product group to use a Bellmac 32 CPU,
and software heavily reworked by a product group.
This is the terminal that was manufactured for general

I'm not sure, but I think the Blit's ROM was very basic,
just enough to be some sort of simple glass-tty or
perhaps smartass-terminal* plus an escape sequence to
let you load in new code.  The Jerq had a fancier ROM,
which was a somewhat-flaky ANSI-ish terminal by default,
but an escape sequence put it into graphics-window-manager
mode, more or less like what had run a few years earlier
on the Blit.

By then the code used in Research had evolved considerably,
in particular allowing the tty driver to be exported to
the terminal (those familiar with 9term should know what
I mean).  In 1127 we used a different escape sequence to
download a standalone program into the terminal and
replace the ROM window manager entirely, so we could run
our newer and (to my taste anyway) appreciably better code.
The downloaded code lived in RAM; you had to reload it
whenever the terminal was power-cycled or lost its connection
or whatnot.  (It took a minute or so at 9600bps, rather
longer at 1200.  This is not the only reason we jumped at
the chance to upgrade our home-computing scheme to use
9600bps over leased lines, but it was an important one.)

The V8 tape was made in late 1984 (I know that for sure
because I helped make it).  It is unlikely to have anything
for the MC68000 Blit, only stuff for the Mac-32 Jerq.
Likewise for the not-really-a-release snapshots from the
9/e and 10/e eras.  The 5620 ROM code is very unlikely to
be there anywhere, but the replacement stuff we used should
be somewhere.

Norman Wilson
Toronto ON

More information about the TUHS mailing list