From: Richard Stover (
Date: Thu Mar 23 2000 - 13:14:33 EST

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    Sorry, I can't test the patch easily. I'm working on my own
    device driver using double-buffered dma to capture a
    continuous stream of video data. We just got the whole
    system (hardward + software) working yesterday.

    As a result I'm not using the normal parport code. I thought
    the patch looked reasonable.

    On my own project, we need to run at something close to
    the rated 2 megabyte/sec capacity of ECP mode. But the
    dma hardware seems to run at 2 microseconds/byte on the
    system I'm using (4 times slower than our goal). Since this is
    the first PC I've looked at in this detail I don't know if this is
    going to be typical. Do you have any experience in this
    area? Are there faster dma controller chips? Or is this set
    by some old standards (like ISA)?


    Richard Stover                       email:
    Detector Development Laboratory
    UCO/Lick Observatory                 Voice: 831-459-2139
    Natural Sciences Bldg. 2, Room 160
    University of California             FAX:   831-459-2298
    Santa Cruz, CA 95064  USA            FAX:   831-426-5244 (Alternate)

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