From: David Forbes (dforbes@as.arizona.edu)
Date: Thu May 16 2002 - 13:14:49 EDT

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    I'm a new poster to this list. I'm a hardware engineer working on a data
    collections system for a radiotelescope which is designed to read data
    from a linear CCD into an industrial PC running RTLinux. The CCD
    interface is all done in a Xilinx FPGA chip connected to an ECP port.
    The data rate needed is about 150 kbytes/sec.

    I have inherited this project from the fellow who designed it, as he is
    no longer able to work on the project. The last status report is that
    the parport driver we have is not capable of reverse channel DMA
    operations at all. This is not good, as we need to have the CPU time
    available for various other activities.

    I read through the parport_pc.c driver code in use and I agree that
    there's no such DMA support. This code file doesn't have a version
    number, but the last update comment is "Various hacks, Fred Barnes,

    So, question time...

    Is there any version of Linux whose parport driver is capable of reading
    in data via DMA?

    If not, is anyone working on this feature?

    Thanks in advance for your help.

    --David Forbes, SMTO, Steward Observatory
      Tucson AZ

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