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Re: Documentation on minixfs and ext2fs



Steve Woodford wrote:

> However, I did write an ACSI based scsi library a while back which should
> be on a.a.u.e in the Programming directory (non-mint). If I recall, it's
> called libscsi1.[tgz/zoo] or something like that. It contains low-level
> ACSI code in it, plus a higher level SCSI command interface. Now, if
> someone wants to volunteer... ;-)
> 
> The only fly in the ointment is that it's not interrupt driven, though it
> could be easilly converted. The problem is that the floppy drive uses the
> same DMA interrupt... :-(  Your solution (below) would not need to be
> DMA interrupt driven.

Another possibility: Steffen Engel (Steffen_Engel@sz.maus.de) has
taken over development of my hard disk driver CBHD. In the current
version, it already supports background transfer for MagiC, and there
are some provisions for background transfers in MiNT. We might be able
to talk Steffen into evolving the background code into an experimental
state.

> The actual drivers (eg. ICD) use the 200Hz tick to implement a timeout
> on the busy-wait for DMA completion, and also the busy-wait between
> SCSI command bytes. The command byte timeout is very short so we would
> have to be *extremely* careful not to pre-empt RWABS too soon otherwise

If you are inside Rwabs(), your code is running in supervisor mode,
and nothing will ever preempt you in all versions of MiNT that I know.
Or are we talking about different problems?
 
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