IDE knowledge anyone?

[Oliver Lehmann]

Oliver Lehmann <lehmann at ans-netz.de> wrote:

> Oliver Lehmann <lehmann at ans-netz.de> wrote:
>
>> Toby Thain <toby at telegraphics.com.au> wrote:
>>
>>> On 2015-12-08 2:16 AM, Oliver Lehmann wrote:
>>>> Hi Warner, hi Brad,
>>>> ...
>>>> I don't intend to use this harddrive anyway, I just fear that I made a
>>>> misstake in my circuit or the code and others intending to use my
>>>> emulator also experiencing problems with their drives too.
>>>
>>> Well, it's certainly interesting. I'm curious now whether your WDC  
>>> AC31600H would work with my PIC code. :)
>>
>> I checked it now with an old 486-DX50 EISA+VLB board (rare combination ;))
>> with a Goldstar Prime 2 and an Acer M5105 ISA Controller. Both detect and
>> work fine with this harddisk. No idea what mode they work but I guess it
>> is PIO 0-whatever only - no DMA involved....
>>
>> Damn this drives me nuts.... either I accept it, or I get a logic analyzer
>> but the cost of such a thing..... :/
>
> But - if the flanks or the timing would not be right - how could the IDENTIFY
> command work without any error? If the flanks would not be straight or /RD is
> not active long enough or whatever - shouldnt return the IDENTIFY an error as
> well? I'd say so......

I just changed the "READ" command to a "FORMAT" command and now the  
drive wants
me to fill up the sector buffer (which I don't do) but at least the command is
accepted and does not immediatly return ERR.... what the heck?

Read Buffer also works after the read-command-error - but now idea if  
the buffer
contains anything which could help me here....

7a424c0c0000100000e158023f001000
00000e004457572d3254393839313032
31392034202020200300000116003332
312e5536333744572043434131333036
48302020202020202020202020202020
20202020202020202020202020201080
0000002f000080020000020000000000
0000000000000001406b300000000704
030078007800a0007800000000000000
00000000000000000000000000000000
...
00000000000000000000000000000000
00000000000000000000000000007800

No idea what this gives me.... the contents are reproducable