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Ipac Usb Vs, Ps/2
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Tiger-Heli:

--- Quote from: microwrx on June 11, 2004, 05:25:38 am ---Most of the USB issues have been with drivers though I think.

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Actually, most of the USB issues have been with BIOS setting and support for USB keyboards in the BIOS (you want to disable it or disable USB 2.0 support, IMS).

--- Quote ---Am I wrong or is the only difference in ordering one or the other the fact that Andy sends the cable for USB or PS2?  So it doesn't really matter what you get if you're willing to buy the other cable as well?

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This is true for the I-PAC/2 or I-PAC/4.  For the MiniPAC with Trackball you have to use USB as you said below, and for the I-PAC VE you have to use USB only.
Tiger-Heli:

--- Quote from: Minwah on June 11, 2004, 07:43:50 am ---I seem to recall that technically in USB mode it can't handle as many simultaneous keypresses, although in game the limit is high enough that it wouldn't be a problem.

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Correct, AFIAK.  However, I would like to make very clear that the limit for USB keyboards is 6 inputs plus 3 modifiers (Ctrl, Alt, Shift, etc.).  This is NOT the same limit as the I-PAC in USB mode.  Referring to my notes:

Depending on board revision, there is a limit of 14, 22, or 16 inputs (plus modifiers such as Shift, Alt, and Ctrl) that the I-PAC supports in USB mode, unlimited in PS/2.
cpepper:
Thank you all for the replys. :D
I didn't realize it was as simple as a cable.
I ordered the usb one and an extra ps/2 cable just incase.

Thanks, again
krick:

--- Quote from: Tiger-Heli on June 11, 2004, 08:37:19 am ---In both cases I sometimes notice a slight delay or "stutter" in USB mode that I don't notice in PS/2 mode.  I feel this is due to the following:

If we are using a keyboard encoder, we are using applications that are expecting input from the keyboard port.
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AndyWarne:
It does not make any difference if you have high bandwidth devices on the same bus as an I-PAC because the I-PAC uses interrupt transfers (as do all USB keyboard devices) and USB hard disk access, for example, simply has to stop and wait because interrupt transfers always get priority.
Yes, keyboard PS/2 to USB adaptors are sometimes not good. The Belkin adaptor is particularly bad and cannot be used for gaming at all. That is not relevant to the I-PAC, it's a device problem, not a USB problem. The I-PAC in USB mode is a native USB device and does not use an adaptor.
Direct-X has a direct path to USB, the IRQ issue is not especially relevant in Windows.
The proof of the pudding: download the Passmark keyboard test from www.passmark.com. This test has a box called "Lag". (I requested this as a new feature, and they added it). Wire two inputs together on an I-PAC, and check this box when you press the button. You will never see a slower figure in the timer display with USB than with PS/2.
Andy
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