Path: utzoo!utgpu!water!watmath!clyde!att!rutgers!cbmvax!andy
From: andy@cbmvax.UUCP (Andy Finkel)
Newsgroups: comp.sys.amiga.tech
Subject: Re: jh1 (bridgeboard harddisk problems)
Keywords: jh1 djmount bridgeboard dpformat
Message-ID: <4504@cbmvax.UUCP>
Date: 17 Aug 88 16:56:15 GMT
References: <880@ozvax.GWD.TEK.COM> <896@ozvax.GWD.TEK.COM>
Reply-To: andy@cbmvax.UUCP (Andy Finkel)
Organization: Commodore Technology, West Chester, PA
Lines: 80

In article <896@ozvax.GWD.TEK.COM> randyh@ozvax.UUCP (Randy Hendry) writes:
>The saga continues...
>onward...  (i.e., now I'm back to the original problem:)

Good.  We're making progress :-)

Let's see if we can continue to do so...

>And did so for every track (cylinder) of the disk (until I stopped it that is).
>There is a good reason for this:  There are no heads (surfaces) 6-10 on this
>disk!  The disk has 6 heads (0-5).  Now non-coincidentally :-( the disk on
>which partition jh0: resides *does* have 11 heads (0-10).  It appears
>that djmount (or dpformat) is using the head information for the first drive
>for all drives.

I think you've got something here.  DJMOUNT is asking the PC side
for the configuration of the hard disk partitions, then constructing
AmigaDOS device nodes.  It sounds like its getting the environment
vector wrong, however.

If you know the partition information, you should be able to use
the standard AmigaDOS MOUNT command, by entering this partition
information into your MountList.

>Seeing this error made me think that I might be able to tell djmount manually
>about the number of heads by using MountList.  I tried a couple of
>combinations, but had no luck.  Djmount doesn't seem to use MountList --
>is this true?

Correct...DJMOUNT is statting the PC side...

>3.  If it is MountList I should use, what are all the magic numbers?
>	(specifically the unit number and cylinder numbers (i.e.
>	do I start with 0 since the partitioning is done on the MS-DOS
>	side, or do I use the actual physical cylinder numbers))?

OK...here's where I slip into theory...(I haven't tried it myself)
Since I know what DJMOUNT and MOUNT are trying to do it should be sound 
theory :-).  I've been told that this procedure works...but 
*haven't tried it*  *You have been warned*

Unit 0 is JH0:, Unit 1 is JH1:

Use the actual physical cylinder numbers.
Put in # heads, surfaces, etc, to match your drive.

Make sure you get it right.  Then Mount it, rather than DJMOUNT it.

(WARNING: If you get the parameters wrong, you'll write somewhere besides
where you intended on your drive...)

>
>4.  (This is more out of curiosity and to show my lack of understanding
>    of all the goings on with the bridgeboard):  why doesn't Janus just
>    use mount and format like the other disk drivers (especially since
>    one can mention the driver to be used in the MountList)?

Because the jdisk author wanted it to be automatic, rather than use
the MountList.  A good ambition, actually.

>Also, I seem to remember someone saying that Janus wouldn't support
>the FFS.  Has that changed, or is it just currently true (i.e. before
>the official 1.3 release)?

If the above method of using the MountList works for you (as several
developers have told us it does) you can use the FastFileSystem
on the Janus disk.  The reason we say its not currently supported
is that DJMOUNT doesn't know the correct magic.  And since moving
FDISK/ADISK parameters into your Amiga side mountlist by hand 
is not the desired mode of operation...

In this case, you would use FORMAT, rather than DPFORMAT.
-- 
andy finkel		{uunet|rutgers|amiga}!cbmvax!andy
Commodore-Amiga, Inc.

"If we can't fix it, it ain't broke."

Any expressed opinions are mine; but feel free to share.
I disclaim all responsibilities, all shapes, all sizes, all colors.