HEADS UP: Check your devices' UDMA settings - *TEMPORARY* *WORKAROUND*

[Basil Chupin]

On 06/04/2011 20:54, Nils Kassube wrote:
> Basil Chupin wrote:
>> On 06/04/2011 17:45, Nils Kassube wrote:
>>> Basil Chupin wrote:
>>>>>> The temporary workaround for this problem is to add to the boot
>>>>>> parameters the following: libata.force=X:80c
>>>> Now all I need is for someone to tell me how to get this fix into
>>>> grub so that it is executed whenever I boot up. I read the grub2
>>>> doco and I am buggered if I can get grub2 to automatically boot
>>>> with this fix in its boot parameters :-( .
>>> Which grub2 doku? I think, [1] sufficiently explains what to do.
>>> Hint: GRUB_CMDLINE_LINUX="libata.force=X:80c"
>> Thanks again, Nils, this did the trick. All devices are now set to
>> their max UDMA settings on boot-up.
> You're welcome!
>
> Out of curiosity I read the Wikipedia article about PATA [1] to find out
> how the cable type is detected. According to that article it is
> important to connect the cable in the right direction, i.e. the blue
> connector should be connected to the controller while the grey and black
> connectors should be connected to the disks. The description seemed a
> bit strange to me and therefore I searched for (an found) an old UDMA
> controller with the necessary 80 wire cable and a PATA disk. I checked
> it and actually if the cable is connected with the black connector at
> the controller and the blue connector at the disk, the controller can't
> detect the cable. I know from the result of your previous thread (Re:
> (FINAL RESULT) -- Need help, please, with burning DVDs) that you have
> opened your box. Could it be that you have connected the 80 wire cable
> the wrong way when you replaced your DVDRW drive? Then the UDMA problem
> would be your hardware and not a software bug.
>
>
> Nils
>
> [1]<http://en.wikipedia.org/wiki/Parallel_ATA#Parallel_ATA_interface>

In reality it would be a bit difficult to make a mistake because, if you 
look closely, the grey (and therefore the black) connector is further 
away from the blue (or even red, which one of my cables has) and so you 
would be rather forcing things a bit to make "ends meet", so to speak in 
a normal setup :-) . But I guess it would not be impossible for some 
people to install the cable the wrong way 'round :-) .

No, in my case the cable(s) have and are installed the right way 'round.

BC

-- 
"I believe what I am programmed to believe."
                     A robot in Futuruma