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USB vs ps\2 style interface
Howard_Casto:
I don't know who's been telling you guys tales, but it's not dangerous in the least to hot-swap ps2 devices. The only danger is that the two keyboards will be so different that it wont' work when you switch em. Same goes for the ipac to controls. It'll work fine. :)
u_rebelscum:
--- Quote ---I'm building an arcade controller for a friend and noticed that both I-pac and Hagstrom both offer USB sollutions. What are the advantages\ disadvantages of using USB over PS\2.
--- End quote ---
ps/2:
pro: supported by DOS
pro: a stable "standard", with stable drivers
con: the standard has no provisions for unplugging during power on, so there is no guaranty that your MB won't fry if you unplug it with your computer on.
pro: >99.99% will not fry your MB if you unplug. I haven't fried any of mine in ~10 years of plugs and unpugs while computer on.
USB:
pro: faster standard than ps/2 (but not usually noticable by humans)
pro: "plug-n-play" (most of the time) while computer is on or off.
con: needs more power than ps/2
con: needs at least another "mini-driver" (ie: the USB driver)
con: newer standard: possiblity of bad drivers is greater than with ps/2
Carsten Carlos:
--- Quote ---So, are you saying that using the Ipac with a PS/2 connector you can still have hot swappable control panels... as long as you make the connections / disconnections between the Ipac and the controls?
--- End quote ---
Sure, that is in my opinion the perfect way to go! Same with the Opti-Pac, the good thing is that the mouse-driver for this one is still at present, wether you disconnect your panel or not! If you'd do this with an USB-plug, windows will always start the recognizing procedure, although this may take only a second I don't think its very elegant. Anyway, if you have more then one of the same USB-devices, the ID's of them might get mixed up additional when you plug them in a different order, at least this is what I would expect.
--- Quote --- don't know who's been telling you guys tales, but it's not dangerous in the least to hot-swap ps2 devices.
--- End quote ---
Heard & read this from a wide varity of sources, it never happened to me though. (I did this too in the earlier days, where I worked as a computer technican)
Wether there is a risk or not, I see absolutely no point why there is a need for swapping it, so better be on the safe side. Disconnecting after the interface is the way to go, so windows don't has to apply any changes at all.
To add to this discussion, when using the I-PAC you get both of two worlds anyway, so you can switch to USB whenever you feel the need for it. Unfortunately you won't get an USB-Optipac for trackballs and spinners so far, I've seen only a one-trackball & keyboard-interface from Hagstrom that features USB, but not PS/2.
u_rebelscum:
--- Quote ---Anyway, if you have more then one of the same USB-devices, the ID's of them might get mixed up additional when you plug them in a different order, at least this is what I would expect.
--- End quote ---
Yes, if you have two or more of the exactly the same devices, windows identifies the first one (re)plugged in as device 1 (or the lowest device number that was assigned to that device type during first install). Since this happens each time you re-plug the devices, you have to make sure you plug them in the same order you installed them if you want to keep them in the same order.
Example: You have two of the same model USB gamepads, one that you hacked into a control panel. You install the hacked gamepad, then the non-hacked one. As long as you don't unplug them, the hacked pad will control player 1, the other player 2. If you unplug both, however, and replug the non-hacked one first and then the hacked second, the non-hacked will now be player 1, and the hacked player 2.
(If, however, the brand, make, or model of the gamepads are different, windows can tell, and the player to gamepad won't change.)
This is true for all USB devices (joystick, mouse, ect) when the computer is on; I'm not sure about what happens if the replug happens with the computer is off.
--- Quote ---Heard & read this from a wide varity of sources, it never happened to me though. (I did this too in the earlier days, where I worked as a computer technican)
Wether there is a risk or not, I see absolutely no point why there is a need for swapping it, so better be on the safe side. Disconnecting after the interface is the way to go, so windows don't has to apply any changes at all.
--- End quote ---
Never hurt my computer by plugging/unplugging the ps/2 with the computer on, but the the reason people and manufactures give this warning is because the ps/2 "standard" does not include protecting the motherboard or ps/2 device if the device is plugged or unplugged while the computer is on. Almost all MBs and devices do pretect themselves against a plug/unplug of a ps/2 device, but since the ps/2 standard does not mention it, the manufactures want to cover their as---, err, moneybooks from complaints of dead computers do to unpluging ps/2 devices with the computer on.
Just like you, I have not had problems with plugging or unplugging a ps/2 keyboard or mouse with the computer on, but some weird combination of ps/2 device and motherboard could result in a fried MB or device since the manufactures don't have a comon standard to rely that the others will follow.
Carsten Carlos:
Thanx, u_rebelscum! :)