As Oliver Fromme wrote ...
> Wilko Bulte wrote in list.freebsd-hackers:
>  > As Oliver Fromme wrote ...
>  > > I once programmed low-level FDC stuff under DOS, so I'm a bit
>  > > familiar with this...  The difference between 1.44 and 2.88 Mb
>  > > floppies is that the latter use 36 sectors per track and twice
>  > > the data rate (1 MBit/s).  So the entry should look like this:
>  > > 
>  > > {36, 2, 0xff, 0x1b, 80, 5760, 1, FDC_125KBPS, 2, 0x6c, 1}
>  > > 
>  > > Actually, there should be a  #define FDC_1MBPS FDC_125KBPS
>  > 
>  > Eh, I guess you mean:
>  > 
>  > {36, 2, 0xff, 0x1b, 80, 5760, 1, FDC_1MBPS, 2, 0x6c, 1}   ?
> 
> No, FDC_1MBPS is not defined (that's why I said that it
> _should_ be defined).
> Actually, FD controllers use a 2bit flag to indicate the
> transfer speed, and traditional controllers interpreted those
> four values as 125, 250, 300 and 500 kbps.  Newer controllers
> dumped the 125 kbps support and interpret the same bits as
> 1000 kbps.  So using FDC_125KBPS is OK.

Ah.. talking about confusing. It's been a long time since I 
had to design a FDC on a SCSI adapter card. Project got scrapped too :-(

> Beware, I have not actually tried this with FreeBSD, and there
> might be bugs that prevent using 2.88 Mb floppies.

I hope to give it a quick try next week.

-- 
|   / o / /  _           Arnhem, The Netherlands        - Powered by FreeBSD -
|/|/ / / /( (_) Bulte    WWW  : http://www.tcja.nl      http://www.freebsd.org


To Unsubscribe: send mail to [EMAIL PROTECTED]
with "unsubscribe freebsd-hackers" in the body of the message

Reply via email to