On Tue, 31 Dec 2002, Bradley Slavik wrote:
I see how to hook up vt220 with db25 f-f null modem
cable, but how does that
get vt420 hooked up? It appears to have some kind of RJ connecton in back,
not DB style. Is there a special cable for that?
It's called an MMJ "Modified Modular Jack" from what I've heard. From
memory, the pinout is approximately:
1 Handshaking
2 Data1 +
3 Data1 -
4 Data2 -
5 Data2 +
6 Handshaking
I think that 1/6 are CTS and DTR, or something like that, but for DEC
gear, hardware handshaking lines shouldn't be needed. Data1/Data2 are
Tx/Rx, I'm not sure which is which, but you can use a null modem cable to
figure that out. If you wanna make a DB25 to MMJ cable:
DB25 MMJ
2 ------------- 2
3 ------------- 5
7 --+---------- 3
\---------- 4
Notice that on the MMJ, pins 3 and 4 are connected together to ground, and
that the 'important' pins are the middle 4 - it's easy to cut a 4wire
modular phone cable in a pinch, trip off the clip on the modular end (like
below) and wire it to a DB25 connector / patch box. Just remember that the
connector won't lock in now, so use something else to hold it in.
_
/ /
_/_/_ _____
| | ==> | |
||||| |||||
or what
model monitor with keyboard and mouse is this thing supposed to work with?
You
need a LK201 or LK401 keyboard and a VSxxx mouse. The same keyboard
(and mouse) as used on the VT[234]xx terminals and the VAXstations.
Where do they hook up to? I see on ebay cables with db15 end and 3 bnc,
keyboard and mouse at the other end. I hook this into back of DEC 3000 where
it has tablet port? or do I need two separate cables, one for monitor from
3w3 connector and one from tablet port for keyboard and mouse?
The cable for the DEC 3000 series has JUST a keyboard/mouse on one end and
DA15 on the other side. Now, be careful, DEC used a DA15 for the console
on most of its machines, but seemed to use a difference cable, and pinout,
for each machine class.
In a typical DEC fashion, in the manual they do not
mention model numbers of
monitor to go with it,
The video timings for the on board Smart Frame Buffer are:
1024 x 786 @ 72 Hz for the 300L
1280 x 1024 @ 72 Hz for the 300, 300X, 300LX
Any sync on green capable multisync monitor can be used. You just need
a 3W3 video cable.
I have plenty of monitors, but not quite sure what you are saying. Say I
have monitor with 13w3 connector on back, then I need 3w3 to 13w3 cable and
monitor is set? Where do keyboard and mouse come into picture? Special cable
plugging into tablet port (DB15) in back of DEC 3000?
If you want a 3w3 -> 13w3 cable (which I havent seen but you could
probably make yourself), make sure the monitor can do sync-on-green. Your
best bet is to find an IBM Powerdisplay (multisync) or authentic DEC
monitor that has 3 BNC's on it, and a standard 3w3 -> BNCs cable.
BTW, the DA15 "Tablet" port isn't a 'tablet port'. That's
supposed to be
a picture of a keyboard ;).
Sorry for so many questions, but I do not know too
much about these machines
(as if that is not obvious). Still I hope to soon have OpenVMS or Linux
running on them.
One last note - even though I'm a Linux fan, I seem to remember that
NetBSD is a better OS to use than Linux (of course OpenVMS is also great,
if you can get software for it to do what you want, or wanna spend $$$ or
time doing it). I've got OpenVMS and NetBSD installed on my DEC 3000/600
- on separate drives.
Pat
--
Purdue Universtiy ITAP/RCS
Information Technology at Purdue
Research Computing and Storage
http://www-rcd.cc.purdue.edu