I just installed the ATAPI stuff without problems on my P100 box with
NCR SCSI, a Mitsumi FX001DE drive and *no* other IDE disks. 

I think Manuel did a great job with his (brand new!) driver:

Mounting works fine on the second try. The first try normally
fails, as advertised in the README with 
acd0(wdc0:0): unit attention 

Reading of not too large files works just fine with regular kernel messages
wdc0: lost interrupt
The data seems to be ok.

Most copies of larger files (>1 MB) still result in I/O errors acompained by
acd0(wdc0:0): illegal length indication 

BTW: In contrast to the REAME the driver seems to be usable also in
ATAPI-only configurations: since I don't use an additional IDE hard disk
I have to run the CD drive alone and in master mode. To get the kernel
with the ATAPI driver linked, a had to put in also the wd* drive line
(could/should be done using the config program, I guess). Anyway, here
is the relevant part of my config file.

ncr*	at pci? bus ? dev ?		# NCR 538XX SCSI controllers
scsibus* at ncr?

sd*	at scsibus? target ? lun ?	# SCSI disk drives
st*	at scsibus? target ? lun ?	# SCSI tape drives
cd*	at scsibus? target ? lun ?	# SCSI CD-ROM drives

fdc0	at isa? port 0x3f0 irq 6 drq 2	# standard PC floppy controllers
fd*	at fdc? drive ?

wdc0	at isa? port 0x1f0 irq 14	# ST506, ESDI, and IDE
controllers
wd*	at wdc? drive ?

atapibus* at wdc?
acd* at atapibus? drive?

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Dirk Duellmann		Tel : +41 22 767 4937
CN Division 513 1-007	Fax : +41 22 767 8630 
CERN			Mail: Dirk.Duellmann@cern.ch
CH-1211 Geneve 23	WWW:  http://wwwcn1.cern.ch/~dirkd/
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