CD-R read errors and OS3.9

[Dietmar]

I have a very strange problem sometimes with GoldED disks (CD-R) shipped to customers: after installation, the software can not be started or libraries don't load. The OS reports "bad hunk".

Investigation invariably shows that the data was corrupted when copied from the CD-ROM. In some cases, it turns out that the user had a wrong MAXTRANSFER settings or a wrong PIO mode selected for the IDE CD ROM (these errors show up with a GoldED CD because it steps through a large file, 64 MB). However, in other cases it is sufficient to just swap the drive: with a different drive, no errors. All users with this problem have OS3.9.

I don't understand how this is possible: if the drive has a problem with a CD-R, it should have a blinking fit and give up later, because there is enough error correction data on a CD-ROM to detect data corruption within the drive . However, in all these cases, installation seems to run fine and no read error is reported (but the copied content is corrupted). Is it possible that there is something seriously wrong with OS3.9? I would expect that any read error on a CD ROM would be reported?

[kd7ota]

It might be possible that the CD burned is corrupt, or your CD-Rom drive hates them CDs and will not read them. I had that problem with new CD rom drives, so I got back to this 24x, and reads any CD I put in it so far.  You can try asking the author to resend you a cd.

[Dietmar]

It might be possible that the CD burned is corrupt

The CD-Rs can not be corrupt per se, they work fine with other drives. I'm using expensive brands (now Verbatim) and a first-class writer (Plextor). It's certainly possible that a specific drive, maybe aging, can not read certain brands of media. BUT:  if a drive can not properly read a CD-R, it usually shows its problems (a blinking light, no response, etc). It does not just deliver corrupted data without any indication to the user. That's why there is so much error correction data on CD ROMS. So I'm still wondering if something is wrong with OS3.9: why does it fail to recognize data corruption ?!

[KennyR]

CacheCDFS could have a bug, since most OS3.9 users would be using this. I seem to recall a bug like this happening to me before when I used one of the 0 ("auto") for a cache setting. Can't remember which, though: I moved to AllegroCDFS a long time ago.

[SilvrDrgn]

Could a mismatch of the "Mask" value between the HD and the CD-ROM drive cause this problem??

(For example, if the Mask value of the HD partition is "0xFFFFFFFC" and the CD-ROM is "0xFFFFFFFE".)

[Stom]

Dietmar wrote:
.......Investigation invariably shows that the data was corrupted when copied from the CD-ROM. In some cases, it turns out that the user had a wrong MAXTRANSFER settings....

What systems are these people running?

I ask because when running on my real Amiga I have no problems what-so-ever with CD's, Where as on my Emulated Amiga (via WinUAE on XP) I have all kinds of problems reading CDs (I cant for example install OS3.9, Freespace or anything like that on it). I went through a whole load of settings and was in contact with the WinUAE developer about it. Finally we came to the conclusion it was down to the Max Transfer setting in the Mount file for the CD (Using CacheCDFS). I knocked a couple of zeros of the Max Transfer and since then I have had no problems reading the disks.

The above only happens within WinUAE though, My real Amiga hs no problems.

[lorddef]

are you complying with ISO standards such as directory depth and filename length?

[Dietmar]

I ask because when running on my real Amiga I have no problems what-so-ever with CD's, Where as on my Emulated Amiga (via WinUAE on XP)

The GoldED CD is specifically targeted at Amigas and WinUAE, so there should be no problem at all (in fact GoldED is developed under UAE).

If other installations have problems, it's typically because content copied from a Windows CD-ROM is automatically read-protected.  Easiest solution: copy such CDs to HD, unprotect everything, then install. There might be some other problems, too: non-standard ISO-CDs with ASCII characters above 128 (e.g. in catalog names) might not show up correctly. And some Amiga names are not permitted under Windows, such as files names made up of spaces (MUI).

[Dietmar]

are you complying with ISO standards such as directory depth and filename length?

Joliet is used (and I'm aware that some old Amiga CD-ROM file systems do not properly support Joliet, a warning is printed on the packaging material).