CD-RW/DVD-ROM Combo

[Charles Steinkuehler]

Rich Edelman wrote:
> Also, be sure DMA is turned on for your cdrw drive! Otherwise you won't be 
> able to burn above 8x without your system getting incredibly choppy, and you 
> absolutely cannot burn above 16x without DMA. DMA will also help when you're 
> watching DVDs with that drive.

Is it possible to use DMA with a 2.4 kernel and ide-scsi?  I tried to 
get this going, but it seems stuck in PIO mode, and I typically can't 
burn over 8x w/o making 'coasters'.

I'm running RedHat 8.0 on an Asus A7N8X-deluxe with a custom 
2.4.21-pre4-ac4 kernel (to properly support the Nforce chipset) with 
USE_DMA=1 in /etc/sysconfig/harddisks and get the following results:

[root at gemini root]# cat /proc/ide/hde/model
Hewlett-Packard CD-Writer Plus 9700
[root at gemini root]# cat /proc/ide/hde/
capacity  driver    identify  media     model     settings
[root at gemini root]# cat /proc/ide/hde/settings
name                    value           min             max         mode
----                    -----           ---             ---         ----
bios_cyl                0               0               1023        rw
bios_head               0               0               255         rw
bios_sect               0               0               63          rw
current_speed           0               0               70          rw
ide-scsi                0               0               1           rw
init_speed              0               0               70          rw
io_32bit                0               0               3           rw
keepsettings            0               0               1           rw
log                     0               0               1           rw
nice1                   1               0               1           rw
number                  0               0               3           rw
pio_mode                write-only      0               255         w
slow                    0               0               1           rw
transform               1               0               3           rw
unmaskirq               0               0               1           rw
using_dma               0               0               1           rw
[root at gemini root]# hdparm /dev/hde

/dev/hde:
  HDIO_GET_MULTCOUNT failed: Invalid argument
  IO_support   =  0 (default 16-bit)
  unmaskirq    =  0 (off)
  using_dma    =  0 (off)
  keepsettings =  0 (off)
  readonly     =  0 (off)
  BLKRAGET failed: Invalid argument
  HDIO_GETGEO failed: Invalid argument

I've tried connecting the CD-burner to one of the on-board IDE 
controllers, and to a Promise PCI-card (what it's currently hooked to) 
with the same results.

-- 
Charles Steinkuehler
charles at steinkuehler.net