Posted by matt(v) on 29, 2000 at 1:06 AM:
In Reply to: Where to put the diodes in a keyboard hack? posted by Rex Rogers on 28, 2000 at 9:13 PM:
First off I have to say that I have never had any luck with diodes, some people swear by them while others say they are a waste of time.
Still if you are determined to go ahead with this here are some basic electronic principals.
First thing is first, diodes only allow current to flow in ine direction. if you put your diodes around the wrong way nothing will work, try it first before you break out the soldering gun and save yourself some grief.
You really only need one diode for each switch/button/direction it matters very little which side of the switch the diode goes on, basically a diode anywhere in the path should work (assuming they work at all).
Since you are only going to be playing games with relitively few buttons you may be able to organise your buttons in such a way to avoid any chance of masking/ghosting.
Someone wrote a guide on how to do this and it should be floating around this site somewhere, check the site map.
Hope this helps
Matt(v)