[Coco] CoCo3 questions / Cloud 9 Super IDE interface

Joel Ewy jcewy at swbell.net
Thu Dec 7 18:11:48 EST 2006


Roger Merchberger wrote:
>>> ...
>>> Going back to the Super IDE does anybody know if it is possible to
>>> transfer .dsk images to the CF card by drag and drop (on a PC with a card
>>> reader) or does the transfer have to be done using a CoCo emulator or a
>>> utility like Omniflop.
>>>       
>
> No, almost no, and no. ;-)
>
> AFAIK, there's no tools that can read/write raw CF drives in Winders, so 
> drag-n-drop is out. Omniflop is only for floppy drives, so it's out...
>   
But what CF cards come unformatted?  They usually have a FAT filesystem
on them when you buy them.  You can certainly drag and drop files onto
CF cards using a GUI file manager in any OS that can read and write a
FAT filesystem.  The problem comes when trying to access the contents of
the .dsk image files on the CoCo.  You have to first be able to read the
filesystem, and second be able to look inside the .dsk image to gain
access to the files contained thereon.  If you are using the CF card as
a hard drive on the CoCo, then you have probably overwritten the FAT
filesystem with what amounts to <=256 CoCo floppy disk images for use
with HDB-DOS, or an OS-9 RBF filesystem.  In that case, the card will
appear unformatted in MS-Windows, or any other OS that doesn't have
support for RBF.  Then of course, you will not be able to drag and
drop.  But the issues essentially remain the same:  you need to find a
filesystem that both operating systems can agree on, and you need to be
able to access the insides of the disk images once they get onto the
CoCo.  Or do something like DriveWire.
> ... but ... Alert: Theoretical (and maybe Heretical ;-) stuff ahead!
>
> However, with (maybe) some minor diddling of the .dsk files to extract 
> *just the raw data*, one could use the dd command in Linux to write the 
> multple "partitions of floppies" to a CF card that can be used in the 
> SuperIDE. I do know that if you set up a CF card w/SuperIDE, you can copy 
> it quite easily with DD and 2 CF readers... you'd need to know the offsets 
> & whatnot for each "virtual floppy" but I believe it would be possible to 
> backup/restore individual floppies.
>
>   
But then you'd still need some software on the CoCo end that can read
the raw disk image files from the CF.  I gather that this is essentially
what HDB-DOS does.  Perhaps with enough detailed info about how it
arranges its floppy images on the drive one could make this work.
> [snip]
>   
>> BASIC ROMs?  If you have an old game cartridge you don't play (or which
>> you can convert to a disk file) you might be able to remove the ROM and
>> use that as a housing for your DriveWire EPROM.  You'd either need to
>> find a 24-pin EPROM, which isn't so common anymore, or hack together a
>> socket converter (which you can probably find instructions for on the
>> Web or in mail list archives) to use a 28-pin EPROM in the cartridge PC
>> board, which is intended for a 24-pin chip.
>>     
>
> A lot of game carts didn't have DIL chips - just the bare IC bonded right 
> to the PC board & a blob of potting material plopped right on top of 'er. 
> IIRC my Downland cart is like that.
>
>   
I have seen some like that too, but I think most of the older ones have
24-pin DIPs.  You can easily tell if you peek through the sliding door
whether there's a DIP chip or a blob.
Ok, here's a quick check of the ROM PAKs I have:
DIP                 BLOB
Quasar Commander    Personal Finance II
MicroPainter        Color File II
Polaris             Typing Tutor
Microbes            Demon Attack
Mega Bug            Color Baseball
Skiing              Androne
Polgergeist         Dungeons of Daggorath
                    Temple of ROM
Rampage             Downland (You do RC, Roger.)
Shanghai            Thexder
                    Arkanoid

So, from this sampling it appears that a little more than half use the
dreaded epoxy blob instead of a DIP IC.  Interestingly, it's not purely
a matter of when the cartridge was introduced either.  Typing Tutor is
from 1980 and is potted, while Rampage is from '89 and uses a DIP. 
Also, Rampage and Shanghai use 28-pin DIPs, which would presumably be
easier to replace with an EPROM.  Maybe different production runs of the
same PAK were different.  But I happen to have 3 DofD carts, and they're
all the same.
Of course, I'm not keen on hacking up any (more..) of my ROM PAKs.  It
was just an idea.  :)
> And: if you did find a 24-pin socket cart, you'd be limited to an 8K DOS 
> without addition hackery to add one more address line from the cardedge to 
> a 16K EPROM.
>   
True.  But unless you can come up with a suitable 24-pin EPROM, you will
already be doing some hackery to wedge the 28-pin chip in there anyway. 
Tacking on one more wire to get the high-order address line isn't going
to make the job significantly harder.  But as Cloud-9 has project boards
and cartridge cases, this is probably best left a hypothetical hack
anyway...

JCE
> Laterz,
> Roger "Merch" Merchberger
>
> --
> Roger "Merch" Merchberger   | "Bugs of a feather flock together."
> sysadmin, Iceberg Computers |           Russell Nelson
> zmerch at 30below.com          |
>
>
>   




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