[Coco] micro drive configuration
fwp at deepthought.com
Wed Oct 14 00:40:16 EDT 2009
While I think I understand what it is that you're trying to do I
don't completely understand the need. These days CF and SD cards are
stupidly cheap and for a coco so large as to be a waste of space. Could
you really fill up a 1gig card with nitros software or data?
I'm not sure if it's worth rewriting coco disk basic and the nitros
the other Frank
On Tue, Oct 13, 2009 at 10:28:25PM -0500, Roger Taylor wrote:
> I have an idea here that I need some feedback on in case I'm missing
> something that might sneak up on me too late.
> Take a 2 gig "memory card" of any kind that the CoCo is interfaced to
> and can access raw sectors for the memory and treat it as a "drive" for
> OS-9 or Disk BASIC. Currently, there may be systems in use that use
> partitions to mark off an OS-9 area and a Disk BASIC area, or possibly
> other areas. I'm guessing that they 256-byte sector controllers so that
> 1/2 of the memory card isn't lost. If the sectors are 512 bytes, then
> the OS probably uses both halves of the sector which requires extra
> overhead... which I'm about to talk about.
> What if the memory card and host controller only dealt with 512-byte
> sectors. Would it be absolutely silly to let OS-9/NitrOS-9 have the
> first half of the sector from LSN to LSN(end) and Disk BASIC have the
> 2nd half of the sector from LSN0 to LSN(end) ? I realize that a
> read/write is involved for every write to retain the other OS'es sector,
> and that a certain amount of speed would be lost for the overhead. The
> benefit would be that a 128mb, 256mb, 1gig, or 2gig (just examples)
> memory card can be dropped in without having to tell the CoCo "OS"
> anything about partitions or areas to stay out of. The idea is to use
> the drive in a parallel fashion and in the simplest fashion, with no
> BASIC config program having to be used to configure the "drives". A 2
> GIG card would yield 1 GIG for OS-9/NitrOS-9 and 1 GIG for Disk BASIC
> virtual drives, but then only 256 drives are ideal so this is what I'm
> trying to work around without wasting any "hard drive" space.
> Of course OS-9 and DIsk BASIC both would have to use only 256 byte sectors.
> ~ Roger Taylor
> Coco mailing list
> Coco at maltedmedia.com
More information about the Coco