IDE knowledge anyone?

[Oliver Lehmann]

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......