Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uwm.edu!rutgers!att!cbnewsl!hojo From: hojo@cbnewsl.att.com (HC Johnson) Newsgroups: comp.sys.atari.st Subject: Re: CD-ROM Summary: SCSI CDROM: now you need a driver and the cd-rom extensions to tos Message-ID: <1990Oct5.184946.16900@cbnewsl.att.com> Date: 5 Oct 90 18:49:46 GMT References: Organization: AT&T Bell Laboratories Lines: 49 In article , gjh@hplb.hpl.hp.com (Graham Higgins) writes: > > What's the current state of play regarding CD-ROM for the ST? > > The reason I ask is that there's a Sony portable CD player available here in > the UK for an affordable 250-odd sterling. It has a built-in SCSI i/f, so in > theory, should be connectable to an ICD DMA-SCSI adaptor. > > Given that it's a Sony, ICD reckon that their driver s/w should be able to > recognise it. > > Is that all that's required, or am I missing a trick somewhere? Shouldn't there > be some kind of hassle like incompatible disk formats (High Sierra vs Low Swamp When you buy the Atari CDROM you get (logicaly) three pieces: 1. the CDROM player (CDAR504) 2. a Driver to talk almose SCSI to tell it what to do. 3. the cd rom extensions to TOS. Really it just called metados and the appropriate format interpreter; e.g. high sierra. I phrased is as above because that is what you get for a PC clone and Atari did a very creditable job of producing the same function. The cd rom extensions are really needed, and quickly show the difference between good applications and others. Remember that if TOS is to read a file it normally has to think interms of a 16 or 32 MB partition, MAX. (forget the hdx 3.01 extensions; they dont apply). The CDROM is likely a singel file system of up to 1200 Mega bytes. The extensions trap all the FS unique system calls, such as FSFIRST, FSNEXT, READ and do it differently. The High Sierra, and other formats have to do with how the large file system is organized. HS looks like TOS (MS/DOS) with out fats. All files are contiguous you only have to find out where they start. When I interfaced the CDAR504 to PC-ditto I, these items all had to be handled for MS/DOS. The bottom line is that you need a heap of neat software to utilize as CDROM player. One way to get it is to buy an Atari CDAR 504. There is still a reason to go with a SONY or Hitachi. Multimedia. This is where voice/music and data are intermixed on the CD ROM. the Atari unit cannot handle this at all! Howard Johnson ATT BELL LABS att!lzsc!hcj hcj@lzsc.att.com