Geez, I can't believe I am asking questions on how to do stuff.

[paigeoliver]

Ok. Bear with me here, I actually have a couple of questions.

#1. When wiring 5 volt or 12 volt lights off the PC power supply do you go ground wire >bulb > bulb > bulb > +5 volts. Or do you separately daisy chain the grounds and +5s. Or is there any actual difference? The more I thought about it, the less difference there seemed to be, because light bulbs have never seemed to care about which power wire is which.

#2. I planned on going a pseudo jamma route with my current project. Would there be any ps2 or USB issues involved with doing the following.

Taking a JAMMA harness and wiring up a keywhiz, PS2 mouse cable, a USB cable, and perhaps a gameport cable to it. So that part plugs into the computer.

Then individual panels would be wired to a JAMMA fingerboard that would plug in and appropriately hit up the keywhiz, USB cable, gameport cable or mouse cable as needed?

A Jamma harness has 56 wires. a max of 22 would be needed for control panel inputs, 2 for ground, 4? USB, 5? mouse port, 1 for +5 volts, and 15 for gameport (total 49). That would leave me 7 extra wires in case I wanted to go crazy and add something else as well.

Anyone forsee any problems?

[Minwah]

#1 Daisy-chain (ie wire in parallel).  If you wire in series the voltage will be split across however many bulbs you have, making them dim.

#2 Um, someone else can have a go...

[LoRDDeVO]

#1 if you go wire>bulb>bulb>bulb> you drop voltage due to the resistance of the bulb each bulb you go across. if you wire them in parallel (all +5 wires to one point and all ground wires to one point( you will keep a contant voltage across the bulbs.

As for the rest of the questions, I have no idea  

[garyh]

Can't help with #2, but for #1 you first suggestion is a series connection and your second a parallel connection.

Series:
+ve - - - - B - - - - - B - - - - - B ----- -ve

Parallel
+ve--------+---------+-----------+
                 B              B                B
-ve --------+---------+-----------+

Series wiring is simpler but in the above example each bulb will only have 1/3 of the total voltage across it, i.e. for a 12v supply each bulb will see 4volts, plus if one bulb blows they all go out. If you are using 12v bulbs they will be dim with only 4v

Parallel wiring gives each bulb the full supply voltage.

Hope this helps.

Gary

[paigeoliver]

Ok, to make question 2 SIMPLER.

Does a computer have any issue with any of the following.

A USB cable hooked up with nothing attached.

A PS2 mouse cable hooked up with nothing attached.

Or a gameport cable hooked up with nothing attached.

I wouldn't THINK so, but I never tried the mouse cable or gameport one.

If there are no problems with the above.

Then would there be any issues in spitting up any of those cables over fatter (IE, JAMMA) wires over part of their length?

[menace]

As far as i can see there wouldn't be any problem with the jamma fingerboard idea--as long as some of the inputs that you wanted to use were plugged in when the machine is powered on.  I think the USB and keywhiz would be fine but you may encounter problems with the ps/2 and gameport since they don't handle being unplugged and plugged back in too well.  I haven't experimented alot with this  so you may get better mileage depending on your OS and the devices you're using.

[Lilwolf]

Yes.. but not as much as they used to.

If you unplug / replug a keyboard in one older boards, you used to be able to blow the keyboard bios.  I haven't seen it for years... but I still wouldn't do it.

Encoders have no trouble.  (so keep the keyboard encoder plugged in 24/7 but break the connections from there.

As for the usb connection.. you can unplug either side of a usb cale at any point.  It was designed for plug'n'play so you should be fine.

but why are you using jamma if you are going to change the interface on it?  Keep the jamma interface normal so you can plug in real boards and create a second wiring harness for the extra buttons.  

Otherwise, you might as well hack some serial cables.  The only real advantage is jamma is compatibility.  Other then that...

[menace]

I was more referring to the point that plugging in a gameport or ps/2 connection will not be recognized if the machine is already on--i wasn't aware you could fry your bios--

And I stopped asking what and why people are doing what they are doing unless its really bizarre (then its just morbid curiosity)--i like to think of this board as the genetic evolution of arcade building-- for every 10 or 100 really bad ideas (and thus hopefully eliminated from the "gene" pool), something will develop (i.e random mutatation) that is really good, further evolving the craft to a higher state  

[Brad Lee]

The PS2 may be a prob, but it may not be.. It's really gonna depend on the motherboard. Seems like msot of the newer ones dont have a problem plugging in and out.
Im not sure if its a simple resitance test to see if its plugged in, or if it actually sends & receives from the logic boards inthe mouse to see if its present

Kinda like in KVM switches- good ones will have power and fool your computer into thinking it's still attached even when you switch to a new comp. Ive had a crap one here at work that was basically just a wiring junction & a rotary switch- if it wasnt turned to the PC you wanted & you rebooted, it wouldnt detect the mouse or keyboard. This was an early era pII

[Vol]

Does a computer have any issue with any of the following.

A USB cable hooked up with nothing attached.

No problem, that would essentially be a 1 port USB hub.

A PS2 mouse cable hooked up with nothing attached.

No problem, however computers do not like PS2 devices to be connected after the operating system has loaded

Or a gameport cable hooked up with nothing attached.

No problem

I wouldn't THINK so, but I never tried the mouse cable or gameport one.

All of the above items can be considered in the same way as extension cables.  Think about it as if you soldered a seperate wire to each individual attachment on the port side.

If there are no problems with the above.

Then would there be any issues in spitting up any of those cables over fatter (IE, JAMMA) wires over part of their length?

PS2 and Analog gamepad cables would probably work without a problem here.  USB may be finicky about impedence.

[hyiu]

I'm currently running XP on a AMD 1.1G machine...

I have a USB cable plugged with nothing... (and I use this loose end to attach my digi cam... so USB... no pblm...)

I hacked gameport sidewinders... and I can plug and unplug them.... (after boot up) and XP will detect them correctly....
(no need for them to be plugged at boot time....)
(although if you daisy chain gameport controls... order is not guaranteed...)
I'm using Mame32 front end and I'll need to restart Mame32 to use the gamepad hack... (not  restarting windows... just mame32..)

and for the PS2 mouse.... my mobo is... when you boot... if you don't plug mouse... then you have no mouse... (assuming you bypassed the keyboard mouse check and let it boot...) if you plug the ps2 mouse in after everything is booted.... the mouse will NOT be detected.....

I have had times when I have booted normally (everything conencted...) then in Windows... (XP) unplug and replug the mouse... (but not for long.... less than a minute...) and things are fine.... no pblm....

hope this helps....

 

[Silver]

Basically there is no harm in connecting/disconnected any of the devices at any time - I've never seen any blown keyboards or such like.

The point about connecting PS2 devices after boot and then disconnecting/reconnecting is significant. KVM (Keyboard-Video-Mouse) switches have special (but simple?) circuits in them so that all the pc's connected to them think they have a permanently connected keyboard/mouse. (The pc's you are not using simply think there is no user input from the mouse/keyboard).  I imagine it is a relatively simple thing (voltage/resistance across a couple of the pins on a PS/2 connector. I believe you can hot plug keyboards into ipacs/keywhiz's so a closer look at one of those may help?

[paigeoliver]

Ok, it all sounds good then.

I didn't plan on hot swapping ANYTHING. I just wanted it all on a single connection, so I (and other people) where not reaching around in the back of the cabinet fumbling to make connections.

I am using a JAMMA harness because, I have several, and the fingerboards are cheap.