CD-ROM on Symbiface 2

[arnoldemu]

Did anyone ever connect a CD-ROM to a Symbiface 2 and load files from it?

I ask because I have looked into this a little.

The CD-ROM is connected to the Symbiface 2 IDE.

However, the CD-ROM uses the ATA "Packet" command set to send SCSI commands via IDE. (SCSI via ATA is ATAPI). ATAPI = ATA Packet Interface.

The CD-ROM also has a different filesystem. It's ISO9660.
(Or Joliet etc but ISO9660 will be enough to start with).

So it's not FAT either by the look of it.

So this means ACMEDOS or SymbOS will not read from it unless they specifically detect the CD-ROM.

Can BonnyDOS load from CD-ROM?
Or the IDE8255 (?) The DOS that has drivers?

Just wondering.

[rpalmer]

hi arnoldemu,

The CD-ROM file structure is more complex the re-writeable media such as hard disc/SD/CF.

It can be done, however for HDOS I would have to alter the way in which I handle any alternate file system which is different to HDOS/AMSDOS and have a second ROM for the alternate filesystem.

At the moment I an updating HDOS to be more flexible, but I may be forced to split it into two ROMs as I am running out of space for a single ROM to hold it all (I have only 62 bytes left for any code).

rpalmer

Attached is a specification for a CD-ROM file system.

[Prodatron]

So this means ACMEDOS or SymbOS will not read from it unless they specifically detect the CD-ROM.

Can BonnyDOS load from CD-ROM?
Or the IDE8255 (?) The DOS that has drivers?

Just wondering.

There is no CD-ROM support for the CPC available. TBH when the SYMBiFACE II has been released 10 years ago CD-ROMs were already outdated
They have ATAPI and ISO9660 drivers on the MSX for IDE devices (since the 90ies IIRC), so it has already been done on a Z80 platform.
Using the ATAPI interface is more complex compared to accessing native IDE devices. I am planning to add an ATAPI driver for SymbOS, but this would only be used for having Iomega ZIP drive/SyQuest EZdrive support - you could have a 3,5" drive which can read 135MB FAT16 media as well.
One problem of the CD-ROM filesystem is, that it is based on 2048byte sectors. As the SymbOS file manager is internally based on 512byte sectors only, it couldn't be supported in a native way.

[Gryzor]

Oh, I must still have my LS-120 Superdisk somewhere...


Used to use it back in '95-'96, going to the university lab with its fat pipes, download all the MAME ROMs and disk images I could find and bring them back home (where I sitll had a 33.6k line)...