Key Ghosting and Blocking question

[aricade]

hey;

Just wanted to run this idea buy you guys maybe some of you have put this into practice and can verify wether this actually works:

I am hacking an old keyboard.  I't does have blocking so I can only ever hit 2 keys and the 3rd key that would create a ghost if pressed will never register...  

Since I couldn't get a enough inputs with out triggering a block (2 player sf2)  I decide to use some keys that fall into a block scenario, BUT I use them for up/down and Left/right controls (and also p1 p2 and coin wich typically not used during gameplay).

So my question is am I right to assume that up/down and left right can not be triggered at the same time?  Or    if a user goes up/down or left/right fast enough, it could register as 2 keys being pressed at the same time   ...

If any one has put this into there controls and know's how well this would work I would love to hear....


Cheers,
Aricade

[RandyT]

I am hacking an old keyboard.  I't does have blocking so I can only ever hit 2 keys and the 3rd key that would create a ghost if pressed will never register...  

Since I couldn't get a enough inputs with out triggering a block (2 player sf2)  I decide to use some keys that fall into a block scenario, BUT I use them for up/down and Left/right controls (and also p1 p2 and coin wich typically not used during gameplay).

So my question is am I right to assume that up/down and left right can not be triggered at the same time?  Or    if a user goes up/down or left/right fast enough, it could register as 2 keys being pressed at the same time   ...

Up/down and left/right should never be able to be activated at the same time.  If you configure everything around this it can work to your advantage.

And, it's quite impossible to move the stick fast enough from one to the other to make both register at the same time.  

RandyT

[aricade]

Cool....

I was pretty sure about this, but I didn't want to build around this theory and then have to hack another keyboard...

Thanx for the lesson in physics!

[SirPeale]

I'm curious.  I've read a few times about making exit for games both up and down at the same time.  How the heck would you do such a thing?

[Tiger-Heli]

I'm curious.  I've read a few times about making exit for games both up and down at the same time.  How the heck would you do such a thing?

That would have been me where you read it.  You can't do this with a keyboard hack or a matrix mode encoder.

What you can do is use diodes and wire a button to the UP and DOWN inputs on a common ground (KeyWiz, I-PAC, MK64) encoder, and then set MAME so UI_CANCEL is "Keycode_UP KEYCODE_DOWN"  But it will only work in programs like MAME that allow multiple key assignments to an input.

This way you can't accidentally exit the game, as the joystick can never activate UP and DOWN simultaneously, but the button can.

I will have a web page about it up, hopefully by next week.