CompuPro floppy controller differences

[Tony Duell]

> 
> On 9/16/2006 at 4:30 PM Allison wrote:
> 
> >Ah, it's using the definitive PC FDC. It was developed well before 
> >PCs standardized. PCs however don't offer much choice and if they did 
> >keep all the FDC features you could put a 8" on a PC and read SSSD!
> 
> You could?!? (if I'm parsing your statement correctly).  IIRC, the original
> PC FDC card had IBM's proprietary data separator on it (several hybrid

I don't recall there being any custom parts. All standard DIL ICs (VCO, 
phase detector circuit, etc). If anyone wants me to check, I have the 
card, and I have the techref (I have found times when the IBM card and 
the Techref don't agreee :-)).

> packagaes) and couldn't read SD/FM to save its life.  It also had the 8272

Rememebr the data rate of 8" SD is the same as that of 5.25" DD. I have 
an idea the data separate _will_ lock to 8" SD (which is still 250kbps), 
and you can then program the FDC chip to do single density operations. I 
have never tried this, though.

> (non "A") part, so it had other problems with "alien" formats.

-tony