I see two possibilities: 1. Connect the mice to a PC in which the X-Server is not activated. If you need to display graphic results, use two networked computers. 2. Use explicit /etc/X11/xorg.conf >From reading man xorg.conf: - Disable hotplugging. - SendCoreEvents off for all identified mice except for one. DISCLAIMER: I didn't actually try the above.
On Thu, 2011-04-07 at 07:04 +0300, yosi yarchi wrote: > Hi > > Regarding the solution of mouse or numeric keypad (with USB hubs), I > have no clear idea about the technical obstacles. I think that main > ones are: > > (1) bypass X system, and direct the events from particular sources > (those mouses or numeric keyboards) to my app. > (2) process the events by myself, with knowledge about the source > device (the particular mouse or numeric keyboard). > > Have you any ideas regarding available support in linux for (1) and > (2)? > > With best regards > Yosi Yarchi > > On 04/06/2011 05:08 PM, Udi Finkelstein wrote: > > I think any analog DAQ based solution will be expensive. Use too > > many analog levels, and it will not be accurate. Use a small number > > of levels, and the price per port for analog connection will drive > > the price too high. > > > > You can try using computer mice. > > cheap 2 button+scroll wheel starts at 17NIS on zap. > > Such a mouse can provide at least 5 events: > > > > right button > > left button > > middle button (scroll wheel press) > > scroll up > > scroll down > > > > You can then take apart the mouse and repackage it, maybe replacing > > the wheel with 3 distinct switches. > > > > Ofcourse you might need powered hubs if you intend to drive 30 mice. > > You could try taking eight 4 port unpowered hubs (also starts at 17 > > NIS on zap), and if you computer has 8 free USB ports (many do these > > days), you could fit 30 mice, and hope that each port can drive 4 > > mice + hub. You will also have 2 spare ports (8*4-30)for the > > console keyboard/mouse. > > > > Another direction would be to use an arduino board. > > http://www.seeedstudio.com/depot/microcontrollers-arduino-compatible-c-132_133.html > > The cheapest $19 board has 14 digital inputs plus 6 analog ones > > which you can treat as digital if you like. > > 20 input pins can serve 5 users (4 input pins/user) or 6 users (3 > > input pins per user if you wire them smartly - 1 qualifier signal > > that is grounded by all 4 switches, and 2 more that are getting a > > 2-bit binary code. > > > > seeedstudio has free worldwide shipping for orders above $50. > > > > Udi > > > > 2011/4/6 yosi yarchi <yosi.yar...@gmail.com> > > Hi > > > > This is interesting idea. However, it support voting between > > 2 options, only, while I need at least 4 options. > > I thought that combination of analog DAQ and 4 push buttons > > with analog output may help here. > > Does someone have an idea about such combination (analog DAQ > > +edge unit)? > > > > With best regards > > Yosi Yarchi > > > > > > > > > > > > On 04/06/2011 10:55 AM, Jason Friedman wrote: > > > I think the best solution would be to use a data > > > acquisition device, either USB or PCI. > > > > > > > > > Measurement computing sell relatively cheap devices, e.g. > > > this USB one for $99: > > > http://www.mccdaq.com/usb-data-acquisition/USB-1024-Series.aspx > > > > > > > > > can measure 24 digital channels (you could get two if you > > > need 30). > > > > > > > > > Each "competitor" could have a small switch, which > > > connects their input line to say a 5V power supply. > > > > > > > > > You can then write a very simple program to detect when > > > each competitor presses their switch > > > (with sub-millisecond accuracy!). > > > > > > > > > These devices apparently have linux support. > > > > > > > > > Jason > > > > > > On Wed, Apr 6, 2011 at 2:44 PM, yosi yarchi > > > <yosi.yar...@gmail.com> wrote: > > > Hi all > > > > > > > > > I need application that will be able to collect > > > and process inputs from 30 (!) competitors, and > > > will display the results very fast. The ideal > > > solution could be to collect the inputs via SMS: > > > each competitor send his answer, the application > > > collect the answers (related to phone number) and > > > process them. However, I can't assume that the > > > competitors have mobile phones (they may be little > > > childs...). > > > > > > > > > I thought to use 30 USB numerical keyboards as > > > input devices, connected with cables to 3 hubs, > > > connected to the computer. > > > > > > However, I don't have experience with USB drivers > > > at linux... > > > > > > > > > Is it feasible? What should be the main guidelines > > > for the solution? > > > > > > > > > With best regards > > > > > > Yosi Yarchi -- No actual electrons, animals or children were harmed by writing this E-mail message. My own blog is at http://www.zak.co.il/tddpirate/ My opinions, as expressed in this E-mail message, are mine alone. They do not represent the official policy of any organization with which I may be affiliated in any way. WARNING TO SPAMMERS: at http://www.zak.co.il/spamwarning.html _______________________________________________ Linux-il mailing list Linux-il@cs.huji.ac.il http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
