IDE knowledge anyone?

[Toby Thain]

On 2015-12-06 4:14 PM, Oliver Lehmann wrote:
>
> Jon Elson <elson at pico-systems.com> wrote:
>
>> On 12/06/2015 02:57 PM, Oliver Lehmann wrote:
>>> Hi,
>>>
>>> I've built a Harddisk-Controller-Emulator for my system which accesses
>>> a IDE (PATA) harddisk with an ATMega in PIO mode. It works like a charm
>>> except for one WD harddisk. The harddisk itself works fine with MS-DOS
>>> 6.22 and FreeBSD but refuses to work with my ATMega.
>>>
>>> On reading or writing a sector, right after the command is issued, the
>>> error bit is set in the status register, and the error register
>>> indicates
>>> an ABRT.
>>>
>> I don't have any specific knowledge of this, but it has to be a timing
>> problem.
>> Something about the timing of the command signals is just different
>> enough that the drive thinks this is wrong.  Sorry I can't give more
>> specific help.
>
> Thought the same and added some 400ns sleeps between each of the cylinder,
> sector, head commands and before I executed the read command... without
> success :(
>

I think Jon is probably on to something.

You can check out the delays in my PIO bit-banging code here:
http://www.telegraphics.com.au/svn/picide/trunk/

I tested it on a few drives & spent a lot of quality time with the 
spec...of course I can't guarantee it would work for your specific 
drive, but it might give you a clue where a delay is missing.

--Toby