Subject: Re: DMA beyond end of ISA with other scsi cards?
To: Michael L. VanLoon -- HeadCandy.com <michaelv@MindBender.serv.net>
From: Justin T. Gibbs <gibbs@freefall.freebsd.org>
List: port-i386
Date: 11/12/1996 23:13:14
>Doesn't this have more to do with the motherboard, than with the SCSI
>card (and the VLB spec, which has so much slop in it, to make some VLB
>boards almost useless for this task)?

Well considering Leonard's sources, I doubt that he is wrong.  Here is
what the Linux Buslogic driver has to say about this:

  /*
    BusLogic BT-445S Host Adapters prior to board revision E have a
    hardware bug whereby when the BIOS is enabled, transfers to/from the
    same address range the BIOS occupies modulo 16MB are handled
    incorrectly.  Only properly functioning BT-445S boards have firmware
    version 3.37, so we require that ISA Bounce Buffers be used for the
    buggy BT-445S models if there is more than 16MB memory.      
  */

>-----------------------------------------------------------------------------
>  Michael L. VanLoon                           michaelv@MindBender.serv.net
>        --<  Free your mind and your machine -- NetBSD free un*x  >--
>    NetBSD working ports: 386+PC, Mac 68k, Amiga, Atari 68k, HP300, Sun3,
>        Sun4/4c/4m, DEC MIPS, DEC Alpha, PC532, VAX, MVME68k, arm32...
>    NetBSD ports in progress: PICA, others...
>-----------------------------------------------------------------------------

--
Justin T. Gibbs
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