22 Aug
2007
22 Aug
'07
3:01 p.m.
I've just bought the base unit (VS240) for a VT240 terminal on E-bay and
know little about it (OK, I know it's a DEC graphics terminal). Perhaps
somebody can enlightent me
1) One site i looked at said a VT240 is a monochrome unit, a VT241 is the
colour version. Is the only difference the monitor? Can I use a colour
monitor with my base unit?
2) On the back are obvious connectors for an RS232 port (DB25), current
loop (8 pin mate-n-lock). There's a DE9 labelled 'PR', presumably a
printer port, also RS232. A RJ11 keyboard socket, I assume an LK201 will
work here (yes?). A BNC which seems ot be composite mono video. And a
DA15 plug, also for a monitor. I assume a VR201 links here, or a V241
with the right cable. Also, can I connect the keybaord to, say, the back
of the VR201, or do I have to use the RJ11 on the terminal itself?
3) How much is known about the insides? Of course I've taken it apart.
It's really easy to get inside, just undo 2 screws on the bottom at the
very front and remove the top cabinet shell (lift it up from the front).
Then release 2 nylatch fasteners and lift up the metal screening cover.
The PSU (a switch-mode unit) is inside the cover. Reach inside and unlug
the PSU ribbon cable from the mainboard and remove the cover/PSU. The
mainboard comes out by releasing 3 more nylatch fasteners.
On this board, there's an 8085, 2681 (dual serial chip), 8251 (USART,
maybe used for the keybaord interface), 7220 (graphics chip) -- along with
what seemms to be much the same circuitry as a Rainbow colour card, there
are a couple of PALs, I've not checked to see if they're the same as the
ones in the 'bow. Pletny of RAM and ROM, and some glue logic. And another
40 pin chip, DC310. For some reason this is saying 'processor' to me. Is
it?
-tony
22 Aug
22 Aug
4:10 p.m.
In article <m1INyGX-000J3MC at p850ug1>,
ard at p850ug1.demon.co.uk (Tony Duell) writes:
1) One site i looked at said a VT240 is a monochrome
unit, a VT241 is the
colour version. Is the only difference the monitor? Can I use a colour
monitor with my base unit?
Doubtful. The electronics for color cost significantly more than the
electronics for grayscale.
3) How much is known about the insides? Of course
I've taken it apart.
It's really easy to get inside, just undo 2 screws on the bottom at the
very front and remove the top cabinet shell (lift it up from the front).
Then release 2 nylatch fasteners and lift up the metal screening cover.
The PSU (a switch-mode unit) is inside the cover. Reach inside and unlug
the PSU ribbon cable from the mainboard and remove the cover/PSU. The
mainboard comes out by releasing 3 more nylatch fasteners.
On this board, there's an 8085, 2681 (dual serial chip), 8251 (USART,
maybe used for the keybaord interface), 7220 (graphics chip) -- along with
what seemms to be much the same circuitry as a Rainbow colour card, there
are a couple of PALs, I've not checked to see if they're the same as the
ones in the 'bow. Pletny of RAM and ROM, and some glue logic. And another
40 pin chip, DC310. For some reason this is saying 'processor' to me. Is
it?
Apart from what's on bitsavers/manx (if there is anything), I don't
know anything about it.
--
"The Direct3D Graphics Pipeline" -- DirectX 9 draft available for download
<http://www.xmission.com/~legalize/book/download/index.html>
Legalize Adulthood! <http://blogs.xmission.com/legalize/>
23 Aug
23 Aug
6:29 a.m.
On Aug 22, 2007, at 7:10 PM, Richard wrote:
But in the case of the VT240, the base unit was designed for
color. Definitely a nice feature.
The VT240 isn't the fastest terminal comm-wise, but I'll tell
ya...it's tough to find a terminal with nicer looking video, in terms
of character definition, sharpness (monitor permitting of course),
etc. They are a real pleasure to use.
-Dave
--
Dave McGuire
Port Charlotte, FL
Farewell Ophelia, 9/22/1991 - 7/25/2007
1) One site i
looked at said a VT240 is a monochrome unit, a VT241
is the
colour version. Is the only difference the monitor? Can I use a
colour
monitor with my base unit?
Doubtful. The electronics for color cost significantly more than the
electronics for grayscale.
12:11 p.m.
1) One site i
looked at said a VT240 is a monochrome unit, a VT241 is the
colour version. Is the only difference the monitor? Can I use a colour
monitor with my base unit?
Doubtful. The electronics for color cost significantly more than the
electronics for grayscale. 
22 Aug
22 Aug
4:42 p.m.
Tony Duell wrote:
1) One site i looked at said a VT240 is a monochrome
unit, a VT241 is the
colour version. Is the only difference the monitor? Can I use a colour
monitor with my base unit?
As far I know it, all of them were color capable. Just
the monitor &
cable was different.
3) How much is known about the insides? Of course
I've taken it apart.
It's really easy to get inside, just undo 2 screws on the bottom at the
very front and remove the top cabinet shell (lift it up from the front).
Then release 2 nylatch fasteners and lift up the metal screening cover.
The PSU (a switch-mode unit) is inside the cover. Reach inside and unlug
the PSU ribbon cable from the mainboard and remove the cover/PSU. The
mainboard comes out by releasing 3 more nylatch fasteners.
Also a space & connector for a modem option.
On this board, there's an 8085, 2681 (dual serial
chip), 8251 (USART,
maybe used for the keybaord interface), 7220 (graphics chip) -- along with
what seemms to be much the same circuitry as a Rainbow colour card, there
are a couple of PALs, I've not checked to see if they're the same as the
ones in the 'bow. Pletny of RAM and ROM, and some glue logic. And another
40 pin chip, DC310. For some reason this is saying 'processor' to me. Is
it?
Should be a T11
23 Aug
23 Aug
12:13 p.m.
Also a space & connector for a modem option.
Ah, so that's what it was for... I noticed the mounting pillars and the
header plug, alnog with a removeable plate on the back to allow access to
connectors on whatever daughterboard went there.
ones in the
'bow. Pletny of RAM and ROM, and some glue logic. And another
40 pin chip, DC310. For some reason this is saying 'processor' to me. Is
it?
Should be a T11 
22 Aug
22 Aug
4:49 p.m.
Tony Duell wrote:
I've just bought the base unit (VS240) for a VT240
terminal on E-bay
and
know little about it (OK, I know it's a DEC graphics terminal).
Perhaps somebody can enlightent me
There's a pocket service guide on Manx (along with a few owner's
manuals).
1) One site i looked at said a VT240 is a monochrome
unit, a VT241 is
the colour version. Is the only difference the monitor? Can I use a
colour
monitor with my base unit?
I believe I was told so by someone back at DEC. But I never got
close enough to one to be able to tell.
2) On the back are obvious connectors for an RS232 port (DB25),
current
loop (8 pin mate-n-lock). There's a DE9 labelled 'PR', presumably a
printer port, also RS232. A RJ11 keyboard socket, I assume an LK201
will
work here (yes?).
I _think_ all the VT2xx terminals shared common keyboards.
A BNC which seems ot be composite mono video. And a
DA15 plug, also for a monitor. I assume a VR201 links here, or a V241
with the right cable. Also, can I connect the keybaord to, say, the
back
of the VR201, or do I have to use the RJ11 on the terminal itself?
3) How much is known about the insides? Of course
I've taken it apart.
On this board, there's an 8085, 2681 (dual serial
chip), 8251 (USART,
maybe used for the keybaord interface), 7220 (graphics chip) -- along
with
what seemms to be much the same circuitry as a Rainbow colour card,
there
Sounds likely.
are a couple of PALs, I've not checked to see if
they're the same as
the
ones in the 'bow. Pletny of RAM and ROM, and some glue logic. And
another 40 pin chip, DC310. For some reason this is saying
'processor' to me. Is
it?
The DEC 1987 Semiconductor Databook just leaped off the shelf to
mention "DCT11" in my ear (Manx has a manual for the T11).
Antonio
No virus found in this outgoing message.
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21/08/2007 16:02
6:04 p.m.
On Aug 22, 2007, at 6:01 PM, Tony Duell wrote:
I've just bought the base unit (VS240) for a VT240
terminal on E-
bay and
know little about it (OK, I know it's a DEC graphics terminal).
Perhaps
somebody can enlightent me
The VT240 is a nice terminal. Good score!
1) One site i looked at said a VT240 is a monochrome
unit, a VT241
is the
colour version. Is the only difference the monitor? Can I use a colour
monitor with my base unit?
Yes, the only difference is the monitor.
2) On the back are obvious connectors for an RS232
port (DB25),
current
loop (8 pin mate-n-lock). There's a DE9 labelled 'PR', presumably a
printer port, also RS232. A RJ11 keyboard socket, I assume an LK201
will
work here (yes?).
Yes, LK201. I've also used LK401s.
A BNC which seems ot be composite mono video. And a
DA15 plug, also for a monitor. I assume a VR201 links here, or a V241
with the right cable.
Yup.
Also, can I connect the keybaord to, say, the back
of the VR201, or do I have to use the RJ11 on the terminal itself?
I don't recall if that works or not...it's easy enough to try,
though.
On this board, there's an 8085, 2681 (dual serial
chip), 8251 (USART,
maybe used for the keybaord interface), 7220 (graphics chip) --
along with
what seemms to be much the same circuitry as a Rainbow colour card,
there
are a couple of PALs, I've not checked to see if they're the same
as the
ones in the 'bow. Pletny of RAM and ROM, and some glue logic. And
another
40 pin chip, DC310. For some reason this is saying 'processor' to
me. Is
it?
DC310 is the part number for the T11, isn't it?
-Dave
--
Dave McGuire
Port Charlotte, FL
Farewell Ophelia, 9/22/1991 - 7/25/2007
9:13 p.m.
In article <A1FE202F-BC54-4431-8308-BABD34273F36 at neurotica.com>,
Dave McGuire <mcguire at neurotica.com> writes:
I stand corrected.
--
"The Direct3D Graphics Pipeline" -- DirectX 9 draft available for download
<http://www.xmission.com/~legalize/book/download/index.html>
Legalize Adulthood! <http://blogs.xmission.com/legalize/>
colour
version. Is the only difference the monitor? Can I use a colour
monitor with my base unit?
Yes, the only difference is the monitor.
23 Aug
23 Aug
12:21 p.m.
On Aug 22, 2007, at 6:01 PM, Tony Duell wrote:
I think so too. I am suprised there wasn't more interest in it. It
actually appeared on E-bay last week, but I didn't bit becuase I couldn't
be sure of being able to meet the seller's deadlines for payment, etc.
Nobody bid, so it was relisted with a lower starting bid. Nobody else bid
this time either, so I got it for about \pounds 5.00.
The seller was a company in north London (behind Ponder's End bus garage,
if you know the area), so I collected it in person and avoided the
postage charges and possible shipping damage. Got some very odd looks
carrying it home on the 'bus, too ;-)
[...]
I've just bought the base unit (VS240) for a
VT240 terminal on E-
bay and
know little about it (OK, I know it's a DEC graphics terminal).
Perhaps
somebody can enlightent me
The VT240 is a nice terminal. Good score! printer port,
also RS232. A RJ11 keyboard socket, I assume an LK201
will
work here (yes?).
Yes, LK201. I've also used LK401s. Also, can I
connect the keybaord to, say, the back
of the VR201, or do I have to use the RJ11 on the terminal itself?
I don't recall if that works or not...it's easy enough to try,
though. ones in the
'bow. Pletny of RAM and ROM, and some glue logic. And
another
40 pin chip, DC310. For some reason this is saying 'processor' to
me. Is
it?
DC310 is the part number for the T11, isn't it?
12:51 p.m.
On Aug 23, 2007, at 3:21 PM, Tony Duell wrote:
I think so too. I am suprised there wasn't more interest in it. It
actually appeared on E-bay last week, but I didn't bit becuase I
couldn't
be sure of being able to meet the seller's deadlines for payment, etc.
Nobody bid, so it was relisted with a lower starting bid. Nobody
else bid
this time either, so I got it for about \pounds 5.00.
I think the reason for the lack of interest is that there are so
many of them out there. I've managed to wind up with about eight of
them in my closet and I don't even know where they all came from.
I'm quite happy to dedicate some closet space to them, though, as
spares for the one on my desk!
Indeed it is, as others have confirmed. I half-thought it was, and
then
thought that nobody would use a PDP11 CPU in a terminal ;-)
:-)
-Dave
--
Dave McGuire
Port Charlotte, FL
Farewell Ophelia, 9/22/1991 - 7/25/2007
I've just bought the base unit (VS240) for a VT240
terminal on E-
bay and
know little about it (OK, I know it's a DEC graphics terminal).
Perhaps
somebody can enlightent me
The VT240 is a nice terminal. Good score! ones in the 'bow. Pletny of RAM and ROM, and some
glue logic. And
another
40 pin chip, DC310. For some reason this is saying 'processor' to
me. Is
it?
DC310 is the part number for the T11, isn't it? 
8:01 a.m.
Tony,
I have one also. Pictures can be found at:
<http://dundas-mac.caltech.edu/~dundas/retro/DEC%20Docs/Terminals/VT240/gallery.html>
At 11:01 PM +0100 8/22/07, Tony Duell wrote:
1) One site i looked at said a VT240 is a monochrome
unit, a VT241 is the
colour version. Is the only difference the monitor? Can I use a colour
monitor with my base unit?
Yes.
2) On the back are obvious connectors for an RS232 port (DB25), current
loop (8 pin mate-n-lock). There's a DE9 labelled 'PR', presumably a
printer port, also RS232. A RJ11 keyboard socket, I assume an LK201 will
work here (yes?).
Yes, I believe the LK201 was the factory configuration.
A BNC which seems ot be composite mono video. And a
DA15 plug, also for a monitor. I assume a VR201 links here, or a V241
with the right cable.
Yes, see the last picture on my site above.
John
2:06 p.m.
On 8/23/07, Tony Duell <ard at p850ug1.demon.co.uk> wrote:
I've just bought the base unit (VS240) for a VT240
terminal on E-bay and
know little about it (OK, I know it's a DEC graphics terminal). Perhaps
somebody can enlightent me
I can try.
1) One site i looked at said a VT240 is a monochrome
unit, a VT241 is the
colour version. Is the only difference the monitor? Can I use a colour
monitor with my base unit?
Yes. You just need the right cable. You can use a VR241, if it's
easier to find in the UK, or back in the day, many folks used an
NTSC-frequency Barco-brand monitor, of a variety that had four BNCs
RGB + Csync).
You could probably use an Amiga-friendly monitor as well, as long as
it takes composite sync, or if you care to break up composite sync to
H and V sync. There's nothing unusual about the VT240 output.
I _think_ it might even produce sync-on-green, which may be what the
mono output is using. ISTR you tell it in the setup menu (which you
enter just like a VT220) that you want the VT240 engine to render in
color vs mono. Check a manual - it should be documented.
2) On the back are obvious connectors for an RS232
port (DB25), current
loop (8 pin mate-n-lock). There's a DE9 labelled 'PR', presumably a
printer port, also RS232.
I believe it's a printer port, but I am reasonably certain it's not
the same pinout as a PC-AT. It should be some DEC pinout.
A RJ11 keyboard socket, I assume an LK201 will
work here (yes?).
Yes.
A BNC which seems ot be composite mono video. And a
DA15 plug, also for a monitor. I assume a VR201 links here, or a V241
with the right cable. Also, can I connect the keybaord to, say, the back
of the VR201, or do I have to use the RJ11 on the terminal itself?
I don't recall that part, but I would expect the keyboard to work in
either place. I doubt anything will be harmed by trying. Most of the
time, DEC was good about that sort of stuff.
3) How much is known about the insides?
Not much, AFAIK.
Of course I've taken it apart.
Of course you have ;-)
I have as well - I got mine by fixing two dead ones. One had a busted
power switch (I replaced it with one off the wall at Radio Shack), the
other had bad EIA line drivers and/or receivers.
On this board, there's an 8085, 2681 (dual serial
chip), 8251 (USART,
maybe used for the keybaord interface), 7220 (graphics chip) -- along with
what seemms to be much the same circuitry as a Rainbow colour card...
Didn't know that. Make sense, though - that's what the engineers were
playing with at the time, so I'm sure somebody borrowed a circuit from
across the hall.
another 40 pin chip, DC310. For some reason this is
saying 'processor' to me. Is
it?
Hmm... I don't know that one off the top of my head. You already have
a processor in there, or else I'd wonder if that was a T-11. Perhaps
you have a T-11 in there as well as an 8085. If so, I'd imagine the
T-11 was the ReGIS engine, and the 8085 does all the I/O.
-ethan
7:50 p.m.
Hi,
Hmm... I don't know that one off the top of my
head. You
already have a processor in there, or else I'd wonder if
that was a T-11. Perhaps you have a T-11 in there as well
as an 8085. If so, I'd imagine the T-11 was the ReGIS engine,
and the 8085 does all the I/O.
Almost....30 seconds with Google confirms that the 8085 was used to handle
text, whereas the T11 handled graphics.
I wonder how similar the 240 is to the GiGi? I recall seeing an 8085 in
there when I took mine apart some 15 years back, but other than that....
TTFN - PEte.
24 Aug
24 Aug
3:49 p.m.
On 8/23/07, Tony Duell <ard at p850ug1.demon.co.uk> wrote:
I have a real DEC VR241 that I use with my Pros and 'Bow.
I've just bought the base unit (VS240) for a
VT240 terminal on E-bay and
know little about it (OK, I know it's a DEC graphics terminal). Perhaps
somebody can enlightent me
I can try.
1) One site i looked at said a VT240 is a
monochrome unit, a VT241 is the
colour version. Is the only difference the monitor? Can I use a colour
monitor with my base unit?
Yes. You just need the right cable. You can use a VR241, if it's
easier to find in the UK, or back in the day, many folks used an NTSC-frequency Barco-brand monitor, of a variety that
had four BNCs
RGB + Csync).
I also have such a Barco. It's actually set up for UK TV rates, but
according to the (excellent) manual, it can be twiddled for NTSC rates as
well.
2) On the back are obvious connectors for an
RS232 port (DB25), current
loop (8 pin mate-n-lock). There's a DE9 labelled 'PR', presumably a
printer port, also RS232.
I believe it's a printer port, but I am reasonably certain it's not
the same pinout as a PC-AT. It should be some DEC pinout. I don't recall that part, but I would expect the
keyboard to work in
either place. I doubt anything will be harmed by trying. Most of the
time, DEC was good about that sort of stuff.
Indeed. It also won't be hard to see if the appropriate pins on the DA15
connect to the RJ11, or indeed if they go anywhere.
-tony
6330
days inactive
6332
days old
14 comments
8 participants
participants (8)
-
arcarlini＠iee.org -
ard＠p850ug1.demon.co.uk -
classiccmp＠memory-alpha.org.uk -
dundas＠caltech.edu -
emu＠e-bbes.com -
ethan.dicks＠gmail.com -
legalize＠xmission.com -
mcguire＠neurotica.com