Subject: Re: SCSI info?
To: Greg Ames <tga@maelstrom.timeplex.com>
From: Allen Briggs <briggs@puma.bevd.blacksburg.va.us>
List: macbsd-development
Date: 07/07/1994 13:17:33
> This machine uses the WD33C93, right? If not, than the following is
> sort of pointless... :-)
Nope. Sorry... It's the NCR 53C96. I have the AMD manual for their
clone. If someone could give me a number for NCR's microelectronics
literature center, that might help, or send me docs ;-) I have their
number on some old 5380 docs, but neither the 800, or the 303 number
work anymore. *sigh*
> So how does the current 5380 driver work? Does it sit in the interrupt
> handler, hogging cycles do access the FIFO at the expense of everything
> else, or is there some "kernel SCSI process" that does this? I don't
> seem to recall MacBSD locking up the system on SCSI i/o...
It locks up the system on scsi I/O, basically, but only on a
block-to-block basis--interrupts disabled... Why couldn't Apple
have done DMA and just written the darn MacOS support for it????
-allen
--
Allen Briggs - end killing - allen.briggs@vt.edu ** MacBSD == NetBSD/Mac **
= Over the years you swam the ocean following feelings of your own [...] =
== It's a shame to have to die to put the shadow on our eyes. We don't ==
=== want to care. Under the bridge. Over the phone. Wind on the Water. ===
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