Subject: Re: macbsd floppy driver, was "Re: "
To: None <hauke@Espresso.Rhein-Neckar.DE>
From: Ken Nakata <kenn@echna.or.jp>
List: port-mac68k
Date: 04/01/1998 10:03:03
On Tue, 31 Mar 1998 19:57:19 +0200,
Hauke Fath <hauke@Espresso.Rhein-Neckar.DE> wrote:
> At 2:53 Uhr +0200 31.03.1998, Ken Nakata wrote:
> >On Tue, 31 Mar 1998 02:27:35 +0200,
> >ehsmswg@aom.ericsson.se (Mats Erik WENNEBERG EHS/GR) wrote:
> 
> >> 4) Does it exist some support for the diskett drive yet?
> >
> >Hauke Fath has succeeded to make an LKM-ized floppy driver that reads
> >and writes 800k diskettes.
> 
> How do you know?  ;)
> 
> In fact, if only I get a night or three to dive into it, the driver LKM can
> go beta in a few weeks. A redesign of vital parts appears to have squashed
> a nasty bug. I'm still unquiet, though: I prefer bugs leaving a mark on my
> hands so I _know_ I hit them. That one disappeared silently instead.

Ur... sorry.  I thought you'd done it already.

> >The real problem is that we don't have any
> >technical documentation on the controller chip (SWIM).  The Mac Linux
> >people seem to be much more active on working to support 1.4M
> >diskettes, so we might be able to use their work when they succeed.
> 
> Ahh, Linux Propaganda...

What!?  I thought you'd know by now I was the last person to engage
such thing... 8-)

> What they do have in Linux/mac68k is a driver framework that can probe the
> IWM and eject the disk, and a long way to go to a "working floppy disk
> driver", and a clueless webmaster... 'nuff said.

Darn!  I admit I had no clue.  I swallowed their words on their web
pages....  Well, not that the driver would have revealed its real
state if I had tried Linux on my Q840av, though.

> >The AV Macs use a different type of controller chip which is similar
> >to the ones used in Intel PCs.  I'm hoping to get the datasheet so I
> >can write a driver for it, but it's not going to work for the non-AV
> >Macs...
> 
> Where'd you get that from? I suppose that - like apparently much of the

Apple TechNotes and DevNotes say it's a custom LSI called New Age, but
the fact is, if you take a look at an AV Mac logic board, you'll
notice that the real identity of the New Age chip is an NEC uPD72070,
a variation of uPD765.  Surprise?  I called NEC's local branch here
and asked for a copy of datasheet.  They say they have it and are
going to send it to me :-)  I hope I will be able to reuse much of
i386 fd driver as it's written for the 765 and its friends.

> other hardware - it cannot be very different from the chip used in the
> PowerMacs. And at least Linux/pmac appears to have a floppy driver. So,
> there must be _some_ documentation floating around.

IIRC, PowerMacs use an IWM-based floppy controller.  Super SWIM or
something.

Later,

Ken