hcj@lzsc.ATT.COM (HC Johnson) (07/06/90)
Notes on the CDAR504. Since the only traffic dealing with the CDAR504 I have seen is my own, I may be speaking in a vacuum. Nevertheless, here are my observations. ATARI has made the CDAR504 available to DEVELOPERS at a very reasonable price. Further, there is evidence of plans to release a demo CD of ATARI software, which implies that sometime dealers will have CD players to use. And Sell? I bought one of these beasties, to see what it would do. 1. I tried it on a Music CD. The CDAR504 plays them. There is even a DA to allow cataloging the tracks of multiple CD's. NEAT! 2. There are no native ATARI CD's yet. (Or least, I don't have access to one). So no comment on their use. 3. There are lots of MS/DOS Data CD's. I got hold of two that are intended for IBM PC's using the Microsoft CD Rom Extensions (MSCDEX). The CDAR504 comes with software that functions similarly to MSCDEX which allows trapping all the GEM OS calls the access files and permits doing it the mscdex way. (Remember we have file systems of == 600 million bytes; far exceeding the gem/ms-dos limits of 32 million bytes). The CD's may be opened from the desktop and files accessed, read, copied, and the like, without limitation. Of course it is hard to copy a file of 200 million bytes to something else. The real problem is that most of the data is compressed and is meant to be read with a program supplied in the directory structure of the CD rom. If the program had been native for an ATARI it would surely work. Unfortunately, the programs are for IBM PC's. 4. I modified PC-Ditto I (a true emulator) to interface to MSCDEX and permit accessing the CDAR504. Now I can access the whole disk and display the encoded information. It is copyable also. 5. Next I got an Apple demo CD. This is a true multi-media (nice buzz word, right!) disk. It has 5 tracks on it, tracks 2 and 3 are speeches describing how great the CD is. These tracks play on my Sony CD player; NOT on the CDAR504. TROUBLE here!! When I try use the CDAR504 to read the contents of the data tracks it refused. Problems with a CDAR504. 1. It turns out that this device internally will access only 2 types of CD rom data structure: A. Music. The magic code is MUSIC, and multiple tracks may be specified. This can be played, but the binary read commands are disallowed. No looking at the bits!!. B. Data. The magic code is DATA. A MSCDEX compatible CD then describes 1 track (containing the whole disk). This can be read, but not played as music. 2. A Multimedia CD (as Apple does it) is structured as: A. The magic code is DATA, but multiple tracks are specified. Think of this as the same as the partitioning of a Hard Disk. The tracks serve to give Start and Extent, not Content. The CDAR504 handles this disk by allowing reads of track 1, and blocking access to the other tracks. A Conclusion. I bought the CDAR504 knowing only that it would play music, and read a yet to be produced Atari CD-rom. I found that it will read and support the common CD-roms for the IBM PC using the MSCDEX software. Finally I found that it will not read multi track data cd's which I suspect covers most of the multimedia ones that combine voice and data. Hopefully, ATARI will see this and consider potential changes in their CDARxxx product line if it is ever released. Howard C. Johnson ATT Bell Labs att!lzsc!hcj hcj@lzsc.att.com
saj@chinet.chi.il.us (Stephen Jacobs) (07/06/90)
I hesitate to speak in the same discussion with Howard, who knows device
drivers awfully well. But from what little I've been able to learn, (another
reason I hesitate--I don't have one) the CDAR504 and its driver software
have been designed for greatest flexibility. Physical and logical disk
access functions are separated as much as possible. The boldness of the
attempt should be viewed in light of the fact that for PC applications, it's
now common to regard the CD ROM, the player and the access software as one
purchase. It's unsafe to presume ANY degree of interoperability. In this
context, the serious problems mentioned aren't all that discouraging. The
ST may yet become the universal CD reader. It clearly isn't there yet.
On a related note: can anyone tell me how to get the documents describing
the CD ROM 'standards'? (High Sierra and ISO something-or-other). I can
see a few applications, but I don't know remotely enough.
Steve J.csbrod@medusa.informatik.uni-erlangen.de (Claus Brod ) (07/06/90)
hcj@lzsc.ATT.COM (HC Johnson) writes: >I bought one of these beasties, to see what it would do. >1. I tried it on a Music CD. The CDAR504 plays them. There is even a > DA to allow cataloging the tracks of multiple CD's. NEAT! An official DA from ATARI? Why didn't I see that all the time? >2. There are no native ATARI CD's yet. (Or least, I don't have access > to one). So no comment on their use. The German software company MAXON collaborated with ATARI Germany and Bertelsmann in producing a CD-ROM containing nearly 200 PD disks. This CD comes with every CDAR504 in Germany; at least that's what ATARI says when I checked the situation some months ago. There's also been a demo CD with some demo software from several German software companies that had been produced for the 1988 ATARI fair in Duesseldorf. > The CD's may be opened from the desktop and files accessed, read, > copied, and the like, without limitation. Of course it is hard > to copy a file of 200 million bytes to something else. The real > problem is that most of the data is compressed and is meant to be > read with a program supplied in the directory structure of the > CD rom. If the program had been native for an ATARI it would > surely work. Unfortunately, the programs are for IBM PC's. Rumours say that there is a software package from a Dutch company that allows some of those DOS CD data to be retrieved on the ST. I think they said something about CDs that can be viewed under DOS with the Microsoft Bookshelf environment. >4. I modified PC-Ditto I (a true emulator) to interface to MSCDEX and > permit accessing the CDAR504. Now I can access the whole disk > and display the encoded information. It is copyable also. > Neat hack! Several readers of my book asked me for something like that. Would you like posting it? How did you do it? > speeches describing how great the CD is. These tracks play on > my Sony CD player; NOT on the CDAR504. TROUBLE here!! Right. The CDAR504 can _not_ handle CDs with combined music and data. I tried with an early firmware version and made suggestions to ATARI in order to change that. (Not very difficult, I think.) Is Mr Schmal listening? What's the current firmware version? ---------------------------------------------------------------------- Claus Brod, Am Felsenkeller 2, Things. Take. Time. D-8772 Marktheidenfeld, West Germany (Piet Hein) csbrod@medusa.informatik.uni-erlangen.de ----------------------------------------------------------------------
smithj@hpsad.HP.COM (Jim Smith) (07/07/90)
There is a native ST CD-ROM available, a collection of PD programs. Last time I checked (late January), it was about $60 from the store called "computer rock" in San Francisco (where its originators work). ---------------------------------------------------------------------------
pwp@iuvax.cs.indiana.edu (Paul Purdom) (07/07/90)
smithj@hpsad.HP.COM (Jim Smith) writes: >There is a native ST CD-ROM available, a collection of PD programs ... from the store called "computer rock" in San Francisco. If someone knowns the contents of this disk, could they post some more information.