some technical questions

Date: Thu Jan 18 2001 - 12:54:31 PST

  • Next message: Henning Meier-Geinitz: "Re: some technical questions"

     I am new to the list and I have some technical questions - would be great
    if someone could explain.

     Basically I have a Canon 1220U scanner and snooped on it's USB packets
    and written a small test program that scans at 75dpi (as packets are
    smaller in this case). Now before doing anything else I wonder whether
    someone can explain to me how scanners look to programmer in general
    and how to interpret register data that I have.

     In particular:
       * I think I found 3 sets of data that looks like gamma. Does it make
         sense ?
       * The scanner is said to be 30 (or 32 ?) bit but I only get 24bit data
         is it supposed to be so ?
       * I also have 2 of 3 sets (one for R, G and B) of bitmasks that seem
         to turn sensors on and off. (when bit is unset the data comes in as
         0 ). What are they for ?
       * there are also some registers that drive the motor - I can use them
         but if there are some general ideas about how they should work I'll
         be happy to listen
       * I don't understand how sensor is switched from 75dpi mode to higher
         dpi mode. (i.e. I can drive the carriage at different resolutions,
         but I don't know how to get the sensor to output higher precision

                         thank you very much

                                   Vladimir Dergachev

    Source code, list archive, and docs:
    To unsubscribe: echo unsubscribe sane-devel | mail

    This archive was generated by hypermail 2b29 : Thu Jan 18 2001 - 12:57:37 PST