Main > Main Forum
Voltage from parallel port
cbmeeks:
Ok, I am an eletronics newbie here.
On my cab, I am going to allow NES games to be played as well as MAME. I thought it would be uber cool to put two NES ports in front of my CP.
So, I bought some NES extension cables (so I wouldn't have to hack my NES controllers) and I got myself a multimeter last night.
I have never used a multimeter before and I know very little about electricity.
I have read that mose parallel ports can't really give the 5 volts needed for the NES controller...and I want two of them.
I plugged a cable into the DB25 port of the computer (parallel) tested:
Pin 6 (power) to Red (positive) cable of the multimeter
Pin 18 (ground) to the Black (ground) cable of the multimeter
The multimeter showed 3.18 (which I assume is volts).
Here are my questions:
1) Is this correct? Is my parallel port not giving the full 5 volts?
2) Can I get hurt from the parallel port? In other words, is there enough juice to cook me? lol
My plans actually call for getting the 5 volts from the PSU....mainly because I might have 2 NES and 2 Atari controller support so I know the PSU should be enough.
3) How dangerous is mucking around with the PSU? Now, I am smart enough not to lick the cables while the thing is plugged up (or unplugged) but what I am wondering is if I accidently touch the cables while powered on or if there is some current hanging around after being unplugged is it going to zap me good.
Thanks!
cb
mattv:
--- Quote ---3) How dangerous is mucking around with the PSU? Now, I am smart enough not to lick the cables while the thing is plugged up (or unplugged) but what I am wondering is if I accidently touch the cables while powered on or if there is some current hanging around after being unplugged is it going to zap me good
--- End quote ---
I suspect this will be the last post we see from cbmeeks :-)
--- Quote ---3) How dangerous is mucking around with the PSU?
--- End quote ---
This can be very dangerous especially coupled with the fact that you know very little about electricity. In fact I would go so far as to say that this is a recipe for disaster.
cbmeeks:
Awww, come on...give me a little credit.
I am pretty good at wiring networking and telephone equipment. :-P
cb
DaveMMR:
Ever see one of those bumper stickers that says "Wiring's no hobby: call an electrician" or something to that effect. Well heed that advice because mucking around inside a PSU is something you do not want to do unless you absolutely know what you're doing. 'ZZZZappp!'
krick:
In order to get any appreciable voltage from a parallel port, you have to tie multiple pins together using diodes.
I built an SNES to Parallel port adapter way back in the day and this is the technique they recommended.
There were several projects like this...
SNESPro
Direct Pad Pro
SNESKey
You can find all about them and more here...
http://snespad.emulationworld.com/
Remember, you need to to more than just hook a controller to a parallel port. There needs to be some sort of drivers installed to allow windows to see the device and either translate the input into keyboard presses, or interface into the DirectInput API.
That parallel port business is a lot of work, you might want to have a look at this instead...
Classic controllers converted to USB for use on your computer:
http://www.sealiecomputing.com/retrozone/