Linked by Hadrien Grasland on Fri 30th Dec 2011 08:24 UTC
Hardware, Embedded Systems In the world of alternative OS development, portability across multiple architectures is a challenging goal. Sometimes, it may be intrinsically hard to come up with hardware abstractions that work well everywhere, but many times the core problem is one of missing information. Here, I aim at learning more about the way non-x86 architectures deal with CPU IO ports, and in particular how they prevent user-mode software from accessing them.
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RE: The ps/2 port
by Doc Pain on Sun 1st Jan 2012 16:58 UTC in reply to "The ps/2 port"
Doc Pain
Member since:
2006-10-08

Also powering things from usb only have a theoretical voltage of 1.1V afaik PS/2 can power an external sound card,video out and a mug warmer on just one line of power.... I will not count that as an advantage, as that might also be its main flaw =D


There is still hardware that "plugs into" the "keyboard input chain", such as barcode scanners and also card readers (as they are for example used in Germany for health insurance chips cards). Power is sometimes provided per PS/2 connector, control signals traditionally came per serial port, and "answers" were sent into the "keyboard input chain" and were immediately available to any program without any further device driver magic.

The PS/2 port still does not claim to be able of hot plugging. While I never had any issues disconnecting and reconnecting my IBN model M keyboard (often using its HIL plug), I've seen keyboard connectors dying several times - with other people, less lucky than me. :-)

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