[Coco] Drivewire question

Aaron Wolfe aawolfe at gmail.com
Sun Jul 26 10:17:26 EDT 2015


I forgot to mention that if you want to talk to individual disks inside a
big file full of disks (like an image of one of the 256 DECB disk
partitions often found on a superide drive), there are tools in the UI to
make that easy.  Mount the big file in any drive, then right click and
choose parameters.  There you can set the offset to any desired sector, or
there is a handy control that will automagically enter the sector for any
given disk number.  This will map requests for LSN X to the specified
offset +X, basically making any individual disk inside the big file appear
to be inserted in the drive.  You can also specify a max LSN limit to
ensure no IO escapes this "window" into the file.

On Sun, Jul 26, 2015, 10:08 AM Aaron Wolfe <aawolfe at gmail.com> wrote:

>
> The protocol uses a full byte to designate the drive number.  AFAIK the
> device descriptors in OS9 also store a full byte for this.  I believe the
> stock 2 or 4 is just an arbitrary limit.  The practical limit depends on
> system ram, in general I'd think more than a handful is probably not worth
> it.  Honestly I never use more than 2, my main OS9 partition in /x0 and
> then /x1 for mounting things I need to copy to/from.
>
>
>
> So... You *could* have /x255 theoretically, I think, but not 0 through
> 255.  And that's probably OK.
>
>
> On Sun, Jul 26, 2015, 9:27 AM Gene Heskett <gheskett at wdtv.com> wrote:
>
>
>  Subject to finding drivewires limitation, either by Aaron piping up, or
> experimentally by our own testing, I would say only that there should be
> at least 7 or 8 as a limit, 8th = /x7, but thats too many descriptors
> for the available sysram.  In my build here, x3.dd is the highest, so
> that limit looks like 4.  That would seem to indicate only 2 bits are
> being used as the drive selection in drivewire.  Aaron?
>
>


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