25 Aug
2014
25 Aug
'14
2:45 p.m.
On Mon, Aug 25, 2014 at 08:42:53AM -0600, emanuel stiebler wrote:
On 2014-08-23 22:59, Larry McVoy wrote:
Nope, all we were doing was muxing a serial line and that was 8051 assembler.
--
---
Larry McVoy lm at mcvoy.com http://www.mcvoy.com/lm
On Sat, Aug 23, 2014 at 03:32:45PM -0400, Clem
Cole wrote:
another guy. We
BEGIN - old guy's memories ....
I see your old guy memories and "raise" my sort of old guy memories.
This is a bell labs blit story. It relies heavily on 7 bit clean stuff.
I'm not entirely sure this ever worked reliably but here is what we did.
I was a grad student at UW Madison and shared an office with had a serial line to the computing center across
the street. We
had a blit,
loved it. We wanted two.
Any chance, you still have any software for the BLIT? 
25 Aug
25 Aug
3:22 p.m.
New subject: networking on unix before uucp
On Mon, Aug 25, 2014 at 9:45 AM, Larry McVoy <lm(a)mcvoy.com> wrote:
On Mon, Aug 25, 2014 at 08:42:53AM -0600, emanuel
stiebler wrote:
still a useful little device today, at 1-2 dollars each...
On 2014-08-23 22:59, Larry McVoy wrote:
Nope, all we were doing was muxing a serial line and that was 8051 assembler. On Sat, Aug 23, 2014 at 03:32:45PM -0400, Clem
Cole wrote:
another guy. We
BEGIN - old guy's memories ....
I see your old guy memories and "raise" my sort of old guy memories.
This is a bell labs blit story. It relies heavily on 7 bit clean stuff.
I'm not entirely sure this ever worked reliably but here is what we did.
I was a grad student at UW Madison and shared an office with had a serial line to the computing center across
the street. We
had a blit,
loved it. We wanted two.
Any chance, you still have any software for the BLIT? 
3:49 p.m.
New subject: networking on unix before uucp
Any chance, you still have any software for the BLIT?
See http://www.brouhaha.com/~eric/retrocomputing/att/5620/5620_faq.html
for information and software.
Warren, maybe that software should make its way into the
TUHS archives too?
I too used a blit for a while. It sure could easily kill a vax/780.
But I really liked it. :-)
Arnold
7:20 p.m.
New subject: networking on unix before uucp
On 2014-08-25 09:49, arnold(a)skeeve.com wrote:
> I too used a blit for a while. It sure could easily kill a vax/780.
emanuel stiebler <emu(a)e-bbes.com> wrote:
Sorry, what do you mean by that?
We had a vax 11/780, with serial lines to various peoples' offices.
BSD 4.1 at the time IIRC, later 4.2. The whole ICS dept. at Ga Tech
was using it - faculty and grad students and lab staff (which I was one
of). The load average was constantly in the single digits.
Now add a few blits, where each physical terminal is doing the load of
4-6 virtual ones (using pseudo-ttys) - a shell on each pty and commands
running on each pty. Bingo! The load average shoots way up.
So, the blit itself wasn't at fault. All the people taking advantage
of what it could let them do, was. At some point they wanted the lab
staff to stop using them because of this...
Arnold
8 p.m.
New subject: networking on unix before uucp
On Aug 25, 2014, at 12:20 PM, arnold(a)skeeve.com wrote:
Now add a few blits, where each physical terminal is
doing the load of
4-6 virtual ones (using pseudo-ttys) - a shell on each pty and commands
running on each pty. Bingo! The load average shoots way up.
So, the blit itself wasn't at fault. All the people taking advantage
of what it could let them do, was. At some point they wanted the lab
staff to stop using them because of this...
Not just the blit. When the Telebit Trailblazer modems came out I was one of the first
Canadian resellers. Demoing those beasts was a tricky proposition. I would haul one out
to a customer site, wire it up to a serial port, then dial up to our office system and let
the beast loose.
They made a great torture test for mid/late-80s tty drivers (and RS-232 hardware
interfaces). Simply 'cu'ing to the office over the modem link, then
'cat'ing a 100 K text file over the link would reliably take a 3B2 to its knees.
After the first couple of demo's – which invariably brought the local staff out of
their offices to ask of the machine had crashed – I learned to schedule these over the
lunch hour, or after office hours :-)
It was quite astounding to see the wide range of performance impacts this had on various
systems. 3B* systems would tip over and die, except for the (built by Convergent Tech)
3B1.
Suns with VME-based serial cards performed quite well. If anyone remembers
'ncc' on the UUCP network, it was a 3/280 with the 16(+?)-port VME serial
expansion board, a Telebit rackmount chassis populated with eight modem cards, and another
eight Convergent NGEN workstations cabled up to do file transfer. Even with all the
Telebits running UUCP flat out at full speed, you couldn't tell it from the
interactive response time on the terminals.
I also used to own an NBI UNIX system. This was an interesting little beast. It was a
QBUS machine in a deskside tower case that really wanted to be a VAX, but it had on a
68010 processor. It ran a very generic port of 4.2BSD (complete with the Pascal
interpreter/compiler!). The machine came with the QBUS equivalent of the VAX DH11 serial
board, but there was a bug in NBI's driver for the board. I lifted the DH11 driver
from the UCB 4.2 tape, changed the name of one struct, compiled and linked a new kernel,
and suddenly it, too, was capable of sustaining several high speed Telebit UUCP links.
(That machine was called 'canada' for anyone still keeping track.)
Fun times :-)
-- {alberta,pyramid,uwvax}!ncc!lyndon
9:06 p.m.
New subject: networking on unix before uucp
Lyndon Nerenberg scripsit:
It was quite astounding to see the wide range of
performance impacts
this had on various systems. 3B* systems would tip over and die,
except for the (built by Convergent Tech) 3B1.
That surely had to do with how many characters the TTY board could cope
with before it had to interrupt the CPU.
--
John Cowan http://www.ccil.org/~cowan cowan(a)ccil.org
If I have not seen as far as others, it is because giants were standing
on my shoulders. --Hal Abelson
9:14 p.m.
New subject: networking on unix before uucp
On Aug 25, 2014, at 2:06 PM, John Cowan <cowan(a)mercury.ccil.org> wrote:
That surely had to do with how many characters the TTY
board could cope
with before it had to interrupt the CPU.
There was the size of the serial chip's hardware buffer (before kicking the device
driver with a hardware interrupt), and the driver itself kicking the kernel via a software
interrupt when the driver's buffers were getting full.
--lyndon
9:17 p.m.
New subject: networking on unix before uucp
On Aug 25, 2014, at 2:14 PM, Lyndon Nerenberg <lyndon(a)orthanc.ca> wrote:
There was the size of the serial chip's hardware
buffer (before kicking the device driver with a hardware interrupt), and the driver itself
kicking the kernel via a software interrupt when the driver's buffers were getting
full.
What mattered was how the driver handed off the data from the bottom end of the driver
code to the kernel. Some drivers were better than others. In most cases (of the serial
ports), the culprit was the device driver.
--lyndon
26 Aug
26 Aug
3:26 a.m.
New subject: networking on unix before uucp
On Mon, Aug 25, 2014 at 01:00:45PM -0700, Lyndon Nerenberg wrote:
It was quite astounding to see the wide range of
performance impacts
this had on various systems. 3B* systems would tip over and die, except
for the (built by Convergent Tech) 3B1.
Sheesh, you people keep bringing up stuff from my past. My buddy Rob
Netzer (used to be a prof at Brown, now works on BitKeeper with me)
had one of those 3B1s. Neat machine. Sort of like a desktop VAX.
We were roommates so we both got to use it, my dim memory is I bought one
too but that might be wrong. What I do know is that we had a compiler
class together where the prof for the class had written a lex/yacc equiv,
we had to come up with a grammar for a subset of Ada and implement it.
Only problem was that the system was an IBM 360 or something miserable
like that.
So Rob went to the prof and said if we write our own lex/yacc equiv can
we do it on our own system? The prof said yes and that was the brief
moment in time where I vaguely understood the difference between recursive
decent parsers and LL(1) and LR(1) (just kidding, I never really got it
other than recursive decent is what I'd write not knowing any better.
I think at one point maybe I got the difference but Rob is light years
ahead of me).
Anyhoo, we wrote an Ada compiler on the 3B1. It didn't do everything,
I think we punted on late binding and some other stuff, but it did a
surprisingly large subset of Ada. It opened my mind to what could be
accomplished in a semester. Industry closed my mind to that because
I learned that all the shortcuts we took wouldn't work in industry.
But still. A couple of guys made a compiler in a semester. Kinda
Unix like.
--
---
Larry McVoy lm at mcvoy.com http://www.mcvoy.com/lm
6:17 a.m.
New subject: networking on unix before uucp
Larry McVoy <lm(a)mcvoy.com> wrote:
On Mon, Aug 25, 2014 at 01:00:45PM -0700, Lyndon
Nerenberg wrote:
I had one too. (Also a trailblazer and then a worldblazer.) The 3B1 ran
SVR2; the BSD networking was available as an add-on with the ethernet
card.
I spent many happy hours working on that box, developing gawk and its
documentation; it was slow enough that you could see algorithmic
differences, e.g. standard diff vs. GNU diff.
It had one of those great AT&T keyboards (as did the blit). The UI
wasn't anything special to write home about though.
For a while there was a separate 3b1.* set of newsgroups and an
archive of stuff at Ohio State; there remains a comp.sys.3b1 group
that still has some activity as new people try to revive some of
these machines and others who had them help out. Someone was writing
an emulator, but I don't think it ever got finished.
Ah, the memories .... :-)
Arnold
It was quite astounding to see the wide range of
performance impacts
this had on various systems. 3B* systems would tip over and die, except
for the (built by Convergent Tech) 3B1.
Sheesh, you people keep bringing up stuff from my past. My buddy Rob
Netzer (used to be a prof at Brown, now works on BitKeeper with me)
had one of those 3B1s. Neat machine. Sort of like a desktop VAX.
3529
days inactive
3530
days old
10 comments
6 participants
participants (6)
-
A. P. Garcia -
arnold＠skeeve.com -
emanuel stiebler -
John Cowan -
Larry McVoy -
Lyndon Nerenberg