PS/2 KVM switch

On Mon, 3 Feb 2014 17:31:09 -0800 (PST), NestorK
wrote:

I
understand that if I go with DVI or HDMI, I can convert to the other
with just a cable adapter. But, if I do go with VGA, does that pretty
much rule out watching videos online in High Definition?

-
A (S)VGA, 15-pin connector is cool, tho also heading backwards, into
the past. Yea, HDMI/DVI stuff is where it's "at" - considering those
bargain 32" and 40" monitors now, television-tuner monitors if you
prefer, are invariably fewer in number with an available VGA
connector. HDMI/DVI at a minimum below SMART-class "televisions,"
iow.

Side note - saw some real nifty cables, $15US or so, on EBAY for
converting from VGAHDMI/DVI;- the thing is, there needs be "active"
electronics going on (voltage potentials), so it's not just a matter
of pin-swapping around stuff from one port standard to another. Way
cool for gear freaks and propeller-twirley heads.

At Tue, 04 Feb 2014 00:38:18 -0500, Flasherly rearranged some electrons to
write:

On Mon, 3 Feb 2014 17:31:09 -0800 (PST), NestorK
wrote:

I
understand that if I go with DVI or HDMI, I can convert to the other
with just a cable adapter. But, if I do go with VGA, does that pretty
much rule out watching videos online in High Definition?

-
A (S)VGA, 15-pin connector is cool, tho also heading backwards, into the
past. Yea, HDMI/DVI stuff is where it's "at" - considering those
bargain 32" and 40" monitors now, television-tuner monitors if you
prefer, are invariably fewer in number with an available VGA connector.
HDMI/DVI at a minimum below SMART-class "televisions," iow.

Side note - saw some real nifty cables, $15US or so, on EBAY for
converting from VGAHDMI/DVI;- the thing is, there needs be "active"
electronics going on (voltage potentials), so it's not just a matter of
pin-swapping around stuff from one port standard to another. Way cool
for gear freaks and propeller-twirley heads.

Some of those nifty cables assume you are using DVI-I, which includes the
analog signals. DVI-D or HDMI does not have those signals present. If
the DVI connector does not have the 4 pins on the right with the 'cross'
around them, then it is DVI-D and the nifty adapter MIGHT not work.

HDMI to VGA would require some kind of active devices.

On Tue, 4 Feb 2014 11:07:07 +0000 (UTC), David wrote:

Some of those nifty cables assume you are using DVI-I, which includes the
analog signals. DVI-D or HDMI does not have those signals present. If
the DVI connector does not have the 4 pins on the right with the 'cross'
around them, then it is DVI-D and the nifty adapter MIGHT not work.

HDMI to VGA would require some kind of active devices.

This one looks dated, and he isn't getting into the guts of what the
cable I described is doing, actively, with electronics...

I do have, btw, that HDMI, believe it is, to the far left of the first
picture in the article, on my newest PCI-E vidcard which I do not use.
(I'm still running 15-pin VGA connectors out from the MB's vidchipsets
to my monitors/televisions, a 32 and 40") That PCI-E videoboard does
work, however, with a standard HDMI-to-VGA connector I've tried;- the
center pictured DVI, I also have on that card, I haven't tried yet on
the one TV I have with DVI. Kinda pointless for me to go the
active-cable VGA-DVI route (rather than straight DVI-DVI).

Half lazy, actually, and I've run my 40" up to its native 1900x1020,
and it doesn't look one crap better, except for making the OS XP/SP3 a
major pain in getting some sort of readable font scheme. Though I may
not have the most pointy eyeballs around, I do sincerely doubt there's
an OS around, yet, capably engineered to take full advantage of
present high pixel resolutions. Damn shame, too, as the 40" was
relatively dirt cheap this past holiday season for last-year's model,
$250 sale.

http://www.pcworld.com/article/19661...onnection.html

No need for HDMI unless planning to watch Blu-ray movies.

DVI also supports the HDCP protocol necessary to view that kind of
protected video content.

With a DVI cable, there's a pure digital signal (VGA is analog) and a
much sharper picture at higher resolutions.

DK wrote:
In article , NestorK wrote:
I phoned up IOGear Tech Support and asked if I could just use a USB to PS/2
adapter cable like this one:

Those USB to PS/2 adapter don't even work reliably work for simple things.
I love my old SGI keyboards. The machine at work does not have PS/2
however. I tried 3 different adapters for it. They all work but far from perfectly.
When typing fast, it frequently goes "crazy", missing letters and/or inserting
random crap.

Pretty sad considering that I have yet to find a mechanical keyboard that would
be as nice as those old SGIs.

DK

http://www.nekochan.net/wiki/Keyboards

"SGI MIPS Systems, PC Keyboards, and KVMs

While many SGI MIPS systems have the ubiquitous PS2 keyboard
and mouse interface, SGI elected to use the less common keyboard
"scan code set 3." Scan code set 2 is more commonly used in the
PC world. While most PS/2 keyboards work when directly connected
to an SGI system, some KVMs seem to translate only a fairly rigid
implementation of scan code 2, resulting in compatibility issues.

Some KVMs have the ability to transparently relay scan code set 3,
some require a jumper or configuration change to do so, and others
apparently pass everything through using the more common scan code 2.
For instance, at least one model of KVM works as long as all of the
systems connected are SGI MIPS systems; if one of the connected
systems is a PC that uses scan 2, as soon as that system is selected,
the key mapping is incorrect for the SGI systems and cannot be reset
without removing the PC and restarting the SGI systems.
"

Maybe the adapter just isn't ready to deal with that.

According to this, the 8042 in the SuperIO does some translation.
Or, at least it can be requested to do translation. I didn't know
that was what it was doing.

http://en.wikipedia.org/wiki/Scancode

Maybe the trick would be, to find out if the mode can be
switched, inside the keyboard. If the keyboard has a name
or model number, you may be able to track down what options
it might support.

On old Sun keyboards, there was a DIP switch hidden underneath,
which changed language mappings or something. A nerdy joke,
was to flip over the keyboard on an unsuspecting user, and
change the DIP switch setting. And then, watch the fun. So
maybe the keyboard has some options in it, somewhere.

Also, on this project

http://rshockley.dyndns.org/indigo.htm

http://rshockley.dyndns.org/schematic.gif

the interface on the right uses a MAX232 level shifter. (I think
that's the end for the SGI machine.) As if the SGI connector
uses RS232 levels, and not 0 to 5V PS/2 levels.
So there are some other differences as well. It's possible
to do RS232 (just barely), using unipolar implementations,
and some kludge like that was done with some Apple
computer I used in the past. Something to do with
the serial port it used.

Somewhere in all that weirdness, is your problem :-)

Paul