Messages in this thread | | | From | Gene Heskett <> | Subject | Advice on high mem ioports needed | Date | Fri, 10 Dec 2004 15:52:57 -0500 |
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Greetings;
I'm trying to cobble up a kernel driver for a card with 3 each 8255's on it, to be used as machine control.
I have supposedly modified it for the 4 byte jumps this card uses between port addresses, and the compile and insmod both seem to work w/o errors when the insmod is given the argument of io=0xf100 (where the cards address is set to via dipswitches) as long as I don't try to register more than the first of 3 chips on this board.
But, running a demo program using port_a of chip 0 thats supposed to cause a motor to step once per second has no effect on the 8255 in question, while a reboot to dos, and a dos based exersize program works just fine.
I think the code I'm fooling with (google for PIO-tar.gz) assumes its working below the 0x3FF barrier, but this card responds to accesses in the 0xF100-0xF12F range. I *think* this might be my problem..
I've looked up the iopl call, but so far no "blinding flash of knowledge" has come my way. Is there a resource available that can enlighten me on this subject? Something that starts at square one as I'm a total dummy vis-a-vis pci bus management functions.
The kernel running is the one from emc's Brain Dead Install, version rc46, kernel=2.4.25-adeos, so the advice should be valid for later 2.4 kernels as I've been told that the 2.6 stuff has a whole new api.
Thanks for any pointers that can be thrown my way.
-- Cheers, Gene "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) 99.30% setiathome rank, not too shabby for a WV hillbilly Yahoo.com attorneys please note, additions to this message by Gene Heskett are: Copyright 2004 by Maurice Eugene Heskett, all rights reserved.
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