21 Feb
2013
21 Feb
'13
3:10 a.m.
On 02/20/2013 10:14 PM, Brent Hilpert wrote:
On 2013 Feb 20, at 11:01 AM, Holger Veit wrote:
I'm not forgetting as I had one of the first Altairs, the 680 was
later. A baudot machine was only a small amount cheaper
and far slower, odd baud rate and code incompatable with the limited
software of the day. In all of LICA
(Long ISland Computer Association) one one person had a baudot machine
(for ham RTTY) and he was
interested in using the computer to replace it.
Baudot for micros was always an oddity.
Allison
Am 20.02.2013 15:04, schrieb Allison:
According to the ref'd manual there is a 'Baudot'/5-level option. To
quote, page 21:
BAUDOT TELETYPE OPTION
The Baudot version of the PROM Monitor .. to support a Baudot
Teletype ..
and convert between Baudot (5-level code) and 7-bit ASCII.
The manual goes on to talk about the 5-bit character translations and
shows a layout of a simple 5-level teletype keyboard.
You guys are forgetting that one of the most affordable
terminal/consoles for the computer hobbyist in the Altair era was a
5-bit teletype. They were obsolete and available as surplus. 8-bit
ASR-33s and the like were still current equipment and not cheap. If
you were lucky you might manage to get your hands on a
7-or-so-year-old surplus video terminal for cheap. A current video
terminal would be another significant expense in addition to the
computer.
On 02/20/2013 04:17 AM, Holger Veit wrote:
This was referred to in the listing as "Baudot".
You're right, this
is not 5 bit baudot/murray code. It is bit-banging tty, in contrast
to an ACIA, though.
What you have to set the terminal to depends on the jumper settings
on the board. It also depends on the monitor itself - there is an
ACIA version which can work with 9600 8n1, but there is also a
Baudot TTY version.
There is no baudot TTY option its a 20ma serial loop option commonly
used for the asr33. And just because we're discussing 5-level
teletypes, if someone wants
one I can supply you with one or more. Pickup Vancouver,B.C.,Canada
region.
>> There is a listing of the monitor and
VTL-2 at
>>
http://www.altair680kit.com/manuals/Altair_680-System_Monitor_Manual-03-Bet…
>> (toplevel page http://www.altair680kit.com/manuals.html).