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IPAC USB or PS2
crashdmj:
Is there any reason why a lot of people choose the IPac for USB over PS2, the only thing I can think of choosing PS2 is that you can leave your USB port open for gamepads.
_Iz-:
PS/2 mode works (slightly) better than USB mode. A standard USB keyboard controller is supposed to only allow a max of 6 simultaneous inputs. Andy has worked around that somehow but I don't know to what extent. I have personally noticed some slight intermittent problems with the I-Pac in USB mode and none whatsoever in PS/2 mode.
Major advantage of USB mode is it's ability to be hotswapped. This is useful for a standalone hotrod style control panel for use on a typical desktop or laptop machine. You plug it in when you want to play and unplug when you don't. No need to shutdown and re-start like you should when attaching a PS/2 device.
If you are making a dedicated machine that will have the controller attached permanently then use the PS/2 mode.
ddoyle1996:
I actually had to use PS/2 since I am running Advance Mame in Dos. I tried using the Ipac in USB mode and enabling the "USB Keyboard" option in Bios, but it didn't work properly (kept pulling one direction or the other).
RandyT:
--- Quote from: _Iz- on May 30, 2003, 01:09:16 pm ---
Major advantage of USB mode is it's ability to be hotswapped. This is useful for a standalone hotrod style control panel for use on a typical desktop or laptop machine. You plug it in when you want to play and unplug when you don't. No need to shutdown and re-start like you should when attaching a PS/2 device.
--- End quote ---
I just want to add something to this. In the old days, hot-swapping a PS2 device was a real bad idea. The old keyboards actually used a lot more power, and there seemed to be less of it available on the port. A blown fuse on the mother board was a common occurance.
Eventually, and keep in mind that this was before USB, the PS2 port was turned to for supplying +5v to external devices. GPS's, joysticks, tablets and other devices had little passthroughs that allowed a device to "leech" it's power from the PS2 port. This was to help make a device as portable and easy to install as possible, and to save money by not needing to include dedicated power supplies.
This led to the PS2 port becoming more robust and less susceptible to damage on newer computers. Just to give an example of this, on my test machine (cheapo Emachines Celeron) I have hot swapped hundreds of times, and never had a problem.
I even had a dead short on a breadboarded project (which cooked a resistor on my project and stunk up the room) and even that didn't kill the port.
Of course, this is all anecdotal and if you have an old system, caution is in order. But newer systems (less than 3 years old) probably won't have much of a problem with a hot-swap on the PS2 port.
YMMV :)
RandyT
Tiger-Heli:
--- Quote from: ddoyle1996 on May 30, 2003, 01:51:31 pm ---I actually had to use PS/2 since I am running Advance Mame in Dos. I tried using the Ipac in USB mode and enabling the "USB Keyboard" option in Bios, but it didn't work properly (kept pulling one direction or the other).
--- End quote ---
Actually, Andy replied to this in a thread and recommended disabling USB keyboard in BIOS and said it should work.
That said, the I-PAC has a limitation of 14 or 15 simultaneous keypresses in USB mode and unlimited in PS/2 mode.
And as Randy T said, I have a 6 or 7 year old computer and have hot-swapped the PS/2 port dozens of times with no ill effects.