On 12/3/2010 3:36 PM, Philipp Thomas wrote:
On Fri, 03 Dec 2010 09:20:58 +0100, Roger Oberholtzer <roger@opq.se> wrote:
Obtaining the PPS over the serial port with this or better accuracy is no problem. Obtaining the same over USB or ethernet is less provable.
No way, at least not for GPS/Time signals! The reason is that serial ports can react to interrupts but USB is polling by the host.
But we are always looking. Serial ports are going the way of the dodo.
Yeah, and sadly so! There is currently no connection for peripheral devices that want to trigger an interrupt. I still wonder why Intel thought no one would need something like this ...
Philipp
USB can use interrupts, as a gander at the Hardware information thingie in Yast will show you. Each of your controllers has an interrupt assigned. In page 3 of this document you see why these are not used much in the real world: http://docs.google.com/viewer?a=v&q=cache:GL4MNLnxjTYJ:www.usb.org/developers/whitepapers/white-4c.pdf+USB+interrupts&hl=en&gl=us&pid=bl&srcid=ADGEESifc9bhWJbL87qzhPiwFLtcydC1DmMEbpEFCO_PpwYLSvObuRkKkzTCgYahjiVncpEXGWPt3l4JJtgqYtrGAlStDMK57CA75XXm7U8Jumu9YYg6-pKxDI4TVV-m9p4Dknq2cF9i&sig=AHIEtbRTY6WUk_T7Bp4BDbtqAOoOp3jJMA Short answer: Blame Microsoft way back in windows 95. -- _____________________________________ ---This space for rent--- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org