Forget USB, we need PS/2 ports


How does he keep a straight face?


73% of statistics are made up on the spot ;)
 
I think there's something true about PS/2 supporting more simultaneous keystrokes. I read quotes like that a lot while I was choosing a keyboard.
 
Yes, but that's only because USB is a retarded protocol capped at 6 simultanious keys "should be enough for everybody."


PS/2 asyncronously report key press/release, and therefor theoretically allows you to press every single key at once, and the OS can see them all.
 
That made me smile - and think of 1988.


Does anyone else remember when mice connected to a serial port and keyboards used fat round 5 pin plugs?


Storage had more flavors too.


Hard drives came in MFM/RLL or 50pin SCSI or the proprietary connectors used in the IBM PS/2 line.


IDE was just starting to show up - but was expensive and rare.


A 20MB hard drive was 'large'.


A 60MB hard drive was enough for a server.


Very high end data centers used 400MB SCSI drives capable of 400Kb/sec reads.


3.5" plastic cased floppies were just starting to take hold, though many were sold as 720K versions and had to have a corner cut off to make them 1.44MB.


5.25" DSDD (Double Sided Double Density) disks were still heavily used.


Optical storage meant an exotic WORM drive. A CD player was just for audio systems.


Backup was all done to tape.


Most professional data centers still used 9 track round reel tapes at up to 128MB per 12" reel.


9600 baud modems were insanely fast.


1200 baud was 'normal' and 2400 baud was 'special'.


Networking meant Token Ring or twisted pair coax ethernet.


VGA was crazy cool high definition and color depth - 640x480 16bit.


Portable meant luggable.


Fun times.
 
^ I still use a keyboard with a DIN-5 connector :p


EDIT: And incidentially; I did get an old serial mouse working with my desktop computer a few months ago :D
 
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^ I still use a keyboard with a DIN-5 connector :p
Me too. I still use an old Cherry mechanical Keyboard, with an Adapter from DIN-5 to PS2 and WITHOUT Windows keys. :D Must be almost 20 Years old that Keyboard and I've got it for free from a friend. Indestructable, these Cherrys and very heavy and stable. Only downside is the missing of Key-lights but I guess this is not possible with oldschool mechanical Keyboards.
 
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I'm a big fan of the IBM Model M keyboard.. I Find a lot of them at work, people just getting rid of them even though they work perfectly. I've got a good collection of them now in my office, too bad taking them home could get me fired..
 
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That is plenty funny. I wonder how many suckers fell for it?
 
I used to use the big PS/2 IBM tactile click keyboards exclusively - then I got a Thinkpad laptop @ 5 years ago and liked the keyboard on it with the ultra nav pointer and touch pad combo. The key throw is nice and has a good feel to it. I bought 4 of them for about $25 each a few years back and put them on all of the computers I use. Now they're insanely priced and I can't even find them with the numeric pad - so some day when I wear them out I'll have to find something else.

https://www.youtube.com/embed/L94qigiAWCg?feature=oembed

Good luck finding one. The PS/2 version is easier to find than the USB. USB version has a two port USB 1.0 hub built in - handy for USB mouse & USB gaming controller.
 
Actually not being able to press more than a few keys simultaniously is called blocking and not ghosting.


Both effects are not caused by the usb spec though, but by the matrix of a keyboard, that can only allow a certain amount of keys in certain rows to be pressed or else they cannot be processed (blocking) or there are some other keys registered even thought you don't press them physically (ghosting).


Blocking can also be a limitation in the keyboardencoderchip.
 
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Actually not being able to press more than a few keys simultaniously is called blocking and not ghosting.


Both effects are not caused by the usb spec though, but by the matrix of a keyboard, that can only allow a certain amount of keys in certain rows to be pressed or else they cannot be processed (blocking) or there are some other keys registered even thought you don't press them physically (ghosting).


Blocking can also be a limitation in the keyboardencoderchip.

You're wrong. The USB-protocol does not allow more than 6 keys pressed at the same time, it's a limitation in the keyboard HID class.


There is n-key rollowver keyboards, but 6 is the max when using them with USB.
 
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How do the blocking free keyboardcontrollers work then, like the ipac? Don't they use the usb hid interface, too?


Edit: Oh, I see, they might use another protocol or something. Still confusing, why the hid protocol would limit simultanious keypresses...
 
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Could a keyboard be logically two keyboards, two usb devices, and therefore double the number of simultaneous keypresses?
 
At least on windows I don't think theres any built in way to interface with two keyboards or mice.
 
Windows definately supports multiple keyboards/mouses. I was just testing an HP wireless keybord and mouse combo on my Windows XP machine at work while the other keyboard and mouse were still connected. Both sets worked perfectly fine.
 
My brother has a black Model M (with the little mouse-nipple) laying around somewhere, I'll have to pick it up the next time I'm home for some good ol' fashioned nostalgia.
 
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I've been having a hard time finding a good PS/2 to USB keyboard adapter for gaming.. seems like almost all of them can't handle simultaneous keypresses well.. so far everyone I bought if your playing a game where your moving forward by holding down W or the Up Arrow and you press a direction key you stop moving forward.. Somebody must make a decent one.
 
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