VIA M1000 mini-itx system installation woes - WRITE_DMA error - cabling?

Arjan Van Leeuwen avleeuwen at
Wed Apr 27 01:11:17 PDT 2005

On 4/26/05, W C <woodycarey at> wrote:
> Hi all,
> I am attempting to install 5.3-R from cd (iso image download)  and
> sysinstall is failing
> to write the chosen (Auto Layout) filesystem to disk, the Toshiba 80G on the
> primary ide channel as master.   The error on vty1 is (from memory) ad0:
> WRITE_DMA, error=84.
> The drive is detected by BIOS as a UDMA100 device.  There is nothing else on
> this IDE channel, and only a cd drive on the other IDE slot.
> A search of -questions reveals this error is a UDMA mismatch, possible
> caused by 80-pin cabling, and fixable with atacontrol ad0 udma33 pio bla bla
> bla.  However, I do not yet have a running system to run atacontrol from, as
> I am installing.  I have rooted around in the bios for an option to force
> the drive to UDMA33 speed, to no avail.  Does anyone know how I can work
> around this problem and  install FreeBSD to this neat little system?  Do I
> have bad cabling, a bad drive, or ???

Yes, I had the same problem.

If this is a 2.5" drive, it probably doesn't have a 80-pins cable.
Force PIO mode for the install by entering at the boot prompt (option
6 in the boot loader menu):
  set hw.ata.ata_dma="0"

After you've installed the system, insert that line into
/boot/loader.conf, and load up "atacontrol mode 0 udma33 udma33" as
early as possible during the boot (try using /etc/rc.early, for
example) to get it up to speed again.


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