26 Jun
2008
26 Jun
'08
8:32 a.m.
I was wondering, what are the differences between the VT100 and the VT102? I've never
seen a VT102, but I have heard that there were some differences having to do with screen
editing. Anyone know?
Similarly, does the VT102 hardware differ from the VT100, or is it just a software
change?
-Ian
26 Jun
26 Jun
9:29 a.m.
On Thu, Jun 26, 2008 at 8:32 AM, Mr Ian Primus <ian_primus at yahoo.com> wrote:
I was wondering, what are the differences between the
VT100 and the VT102? I've never seen a VT102, but I have heard that there were some
differences having to do with screen editing. Anyone know?
Similarly, does the VT102 hardware differ from the VT100, or is it just a software
change?
-Ian
http://www.vt100.net/vt_history
VT100
Digital's first ANSI-compliant terminal, introduced in August 1978.
The VT100 was more of an architecture than a simple terminal. There
are two display formats: 80 columns by 24 lines and 132 columns by 14
lines. A separate advanced video option was required to display 24
lines in 132-column mode; this was standard on the VT102 and VT131.
VT101 & VT102
Cost reduced, unexpandable VT100s. The VT102 has the advanced video
option; the VT101 doesn't.
9:45 a.m.
--- On Thu, 6/26/08, Glen Slick <glen.slick at gmail.com> wrote:
VT101 & VT102
Cost reduced, unexpandable VT100s. The VT102 has the
advanced video
option; the VT101 doesn't.
There were more differences than just that though. The built-in AVO is a nice touch, but
from what I've read, there was a slight protocol change as well. AFAIK, the AVO just
added the extra RAM that the terminal needed to be able to store and display more than
about 1,920 characters at once. (80*24=1920, 1920 characters/132 columns= about 14.5, it
would be silly to display half a line, so 14 lines.)
-Ian
9:46 a.m.
--- On Thu, 6/26/08, Glen Slick <glen.slick at gmail.com> wrote:
VT101 & VT102
Cost reduced, unexpandable VT100s. The VT102 has the
advanced video
option; the VT101 doesn't.
There were more differences than just that though. The built-in AVO is a nice touch, but
from what I've read, there was a slight protocol change as well. AFAIK, the AVO just
added the extra RAM that the terminal needed to be able to store and display more than
about 1,920 characters at once. (80*24=1920, 1920 characters/132 columns = about 14.5, it
would be silly to display half a line, so 14 lines.)
-Ian
6:42 p.m.
On Thu, Jun 26, 2008 at 08:32:26AM -0700, Mr Ian Primus wrote:
I was wondering, what are the differences between the
VT100 and the VT102? I've never seen a VT102, but I have heard that there were some
differences having to do with screen editing. Anyone know?
Similarly, does the VT102 hardware differ from the VT100, or is it just a software
change?
My recollection is that the VT102 always has features that are described
as options for the straight-VT100. One I recall is that if you put a
VT100 into 132-column mode, it doesn't have enough video memory for all
24 lines, so you get a short screen. One of the hardware options (AVO?)
adds enough memory to give a full screen in wide mode.
I think that must be there because of the cost of SRAMs when the VT100 was
introduced (weighting the costs in favor of the majority 80-column usage
of the day). I don't recall seeing any clones with that limitation, just
the original VT100.
There are probably a couple other minor differences. Somewhere, someone
should have some DEC literature on the subject.
-ethan
--
Ethan Dicks, A-333-S Current South Pole Weather at 27-Jun-2008 at 01:30 Z
South Pole Station
PSC 468 Box 400 Temp -91.3 F (-68.5 C) Windchill -131.0 F (-90.6 C)
APO AP 96598 Wind 9.7 kts Grid 61 Barometer 672.1 mb (10928 ft)
Ethan.Dicks at usap.gov http://penguincentral.com/penguincentral.html
8:34 p.m.
The vt100 PS was for that unit only ( and 105 and 125). I don't recall the #
now. The 101, 102, 131,132 and others all used the same PS and the boards
were interchangable. The 100 had a "backplane" type connecter, the other ps
had about a 10 pin connecter.
The 100 could be upgraded to a 105 or 125.
I think the vt103, which had a q-bus backplane had a ps of its own, along
with the PDT110.
On Thu, Jun 26, 2008 at 8:42 PM, Ethan Dicks <ethan.dicks at usap.gov> wrote:
On Thu, Jun 26, 2008 at 08:32:26AM -0700, Mr Ian
Primus wrote:
I was wondering, what are the differences between
the VT100 and the
VT102? I've never seen a VT102, but I have heard that there
were some
differences having to do with screen editing. Anyone know?
Similarly, does the VT102 hardware differ from the VT100, or is it just a
software
change?
My recollection is that the VT102 always has features that are described
as options for the straight-VT100. One I recall is that if you put a
VT100 into 132-column mode, it doesn't have enough video memory for all
24 lines, so you get a short screen. One of the hardware options (AVO?)
adds enough memory to give a full screen in wide mode.
I think that must be there because of the cost of SRAMs when the VT100 was
introduced (weighting the costs in favor of the majority 80-column usage
of the day). I don't recall seeing any clones with that limitation, just
the original VT100.
There are probably a couple other minor differences. Somewhere, someone
should have some DEC literature on the subject.
-ethan
--
Ethan Dicks, A-333-S Current South Pole Weather at 27-Jun-2008 at 01:30
Z
South Pole Station
PSC 468 Box 400 Temp -91.3 F (-68.5 C) Windchill -131.0 F (-90.6
C)
APO AP 96598 Wind 9.7 kts Grid 61 Barometer 672.1 mb (10928
ft)
Ethan.Dicks at usap.gov
http://penguincentral.com/penguincentral.html
7:18 p.m.
The vt100 PS was for that unit only ( and 105 and 125). I don't recall the #
now. The 101, 102, 131,132 and others all used the same PS and the boards
were interchangable. The 100 had a "backplane" type connecter, the other ps
had about a 10 pin connecter.
And IIRC the PSUs are very different, the VT100 having a true
switch-mode unit, while the VT101. etc has a mains transformer (and maybe
switching regulators on the secodnary side of that).
From what I rememebr theVT100 is a fairly modular
design. You can add the
AVO [1] There's an ingenious edge connector that can
take a board that
electrically sits between the VT100 and the serial line (when that board
is not plugged in, the contacts in the connector touch, connecting the
VT100 to the serial line), and so on. The VT101, etc, was all on one
board, it wasn't really expandable.
-tony
5804
days inactive
5805
days old
6 comments
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