I have a used HP 7100 cd-writer and i'm trying to make it work .
After creating a test iso image wirh mkisofs , i used 
" cdrecord -v dev=/dev/rcd0d /cd.iso   " command to burn the cd and i
get the following: 

Feb 25 18:17:57 rhino /netbsd: pciide0:1:0: lost interrupt
Feb 25 18:17:57 rhino /netbsd:  type: atapi tc_bcount: 60 tc_skip: 0
Feb 25 18:17:57 rhino /netbsd: pciide0:1:0: bus-master DMA error:
missing interr    upt, status=0x20
Feb 25 18:17:57 rhino /netbsd: pciide0:1:0: device timeout, c_bcount=60,
c_skip=    0
Feb 25 18:17:57 rhino /netbsd: cd0: transfer error, downgrading to PIO
mode 3
Feb 25 18:17:57 rhino /netbsd: cd0(pciide0:1:0): using PIO mode 3
Feb 25 18:21:57 rhino /netbsd: pciide0:1:0: lost interrupt
Feb 25 18:21:57 rhino /netbsd:  type: atapi tc_bcount: 28 tc_skip: 0
Feb 25 18:21:57 rhino /netbsd: pciide0:1:0: reset failed
Feb 25 18:22:02 rhino /netbsd: pciide0:1:0: lost interrupt
Feb 25 18:22:02 rhino /netbsd:  type: atapi tc_bcount: 0 tc_skip: 0
Feb 25 18:22:02 rhino /netbsd: pciide0:1:0: piomode timed out
Feb 25 18:22:02 rhino /netbsd: pciide0:1:0: reset failed


I believe that the problem is with DMA transfers . i compiled a new
Kernel with 

pciide* at pci? dev ? function ? flags 0xf
cd*     at atapibus? drive ? flags 0xf 

but no change . Am i wrong ?