CDAudio Problems

[Gerry Gruber]

Hi. Looking for some advice. Have Knoppix HD installed (April 18 version). I can read data files off my cdrom but can't play cdaudios. (It is also a DVD/CD-R if that makes any difference - I haven't yet checked to see whether there are any problems with the DVD or CD-R capabilities). The sound card works fine, as MP3's play OK. Do I need to have a line in the fstab for cdaudio, different from cdrom? From what I read, if the cdrom is working fine, the cdaudio should be automatic, in that it doesn't even need to be mounted. Here's what my fstab entry for my cdrom looks like:

/dev/hdc /mnt/cdrom iso9660 noauto,ro,user,noexec 0 0

The dmesg file confirms that hdc is the correct device:

hdc: HL-DT-ST RW/DVD GCC-4120B, ATAPI CD/DVD-ROM drive

However, it also talks about a SCSI host adapter a few lines lower:

scsi0 : SCSI host adapter emulation for IDE ATAPI devices

And, so I am wondering whether I need another line in the fstab, or whether I need to point to a different device than hdc? Any suggestions would be much appreciated. (P.S. I read previous posts going back several months and the various HOW TOs, to no avail.)

Gerry

[Gerry Gruber]

I just discovered that if I use the physical controls on the front of the actual cdplayer, then it plays cdaudios. So, the system is clearly capable of reading the cdaudios and producing the sounds. However, it doesn't appear to be controlable via software, i.e., KsCD. Strange. What are some other cdaudio players that have worked well in Knoppix for others?

[aay]

DVD's and CDRWs are configured with scsi emulation. Perhaps your fix will be as simple as mine was. I found that If I ran aumix the cd volume was, by default, turned down to far to be heard. CD's played but they were not heard. Run aumix and try adjusting the volume levels (especially the cd volume). Since your, post contained no error messages, it might just be that simple.

[Gerry Gruber]

Yes, the volume was quite low, and I was able to adjust it with Kmix. And, as I indicated in my follow-up post, the bottons on the front of the cddrive do actually make the cdaudio play cds through the system speakers. However, I can't control the cdaudio via any software program (or at least those I tried so far) - such as starting and stopping, changing tracks, etc.

Re. the SCSI emulation, how does that affect how the cd write and dvd work? For example, would the device names be different in the fstab and/or mount commands (i..e., /dev/hdc worked for the cdrom - should I have additional fstab statements with different devices for the cdwrite and dvd)? In the K3b setup program (cdwriter), it says that it can't find my cdwriter. It sounds like I need to enable scsi emulation. But when I issue the "modprobe ide-scsi command, it tells me there is no such module. Is this really the case with Knoppix (April 18 release), and if so what would be the easiest way to get the scsi emulation module, assuming I need it?

[rickenbacherus]

Yes, the volume was quite low, and I was able to adjust it with Kmix. And, as I indicated in my follow-up post, the bottons on the front of the cddrive do actually make the cdaudio play cds through the system speakers. However, I can't control the cdaudio via any software program (or at least those I tried so far) - such as starting and stopping, changing tracks, etc.

Do you use analog or digital out from your dvd/cd-r? You might have some luck this way: Open a term and enter /etc/init.d/alsa-autoconfig



Re. the SCSI emulation, how does that affect how the cd write and dvd work?

It won't work w/out SCSI emulation.


For example, would the device names be different in the fstab and/or mount commands (i..e., /dev/hdc worked for the cdrom - should I have additional fstab statements with different devices for the cdwrite and dvd)?

No it's the same device. If it uses SCSI emulation then it would be on the SCSI BUS right? How do you see what's on the SCSI BUS?

cdrecord -scanbus

You can 'link' something like /dev/cdrom to your DVD/CD-R like this:

ln -s /dev/cdrom /dev/scd0

Then do this:

ls -al /dev/dvd

It should tell you that /dev/dvd is a symbolic link pointing to /dev/scd0 and who has permissions for this device.


In the K3b setup program

Do not- I repeat do not use the K3b setup- it will wreck your fstab. So you say "but I already did". You could search and probably figure it out, you could post your fstab OR you could boot the Knoppix cd and copy the fstab from there. It might still be OK tho if K3b setup failed to work. Using the search function I found this (http://www.knoppix.net/forum/viewtopic.php?t=2107#9962) post on how to set up K3b


(cdwriter), it says that it can't find my cdwriter. It sounds like I need to enable scsi emulation. But when I issue the "modprobe ide-scsi command, it tells me there is no such module. Is this really the case with Knoppix (April 18 release), and if so what would be the easiest way to get the scsi emulation module, assuming I need it?

That is correct- there is no ide-scsi module as it is already compiled into the kernel. You just need to let LILO know that you want it to start SCSI emulation. There should already be a line in /etc/lilo.conf that looks like this:

append="hda=ide-scsi hdb=ide-scsi hdc=ide-scsi"

If it's not there add it. This line can include additional parameters that you want to pass on boot i.e. noscsi nopcmcia apm=power-off. Do a:

dmesg | less

and you should see that the kernel is starting SCSI emulation.

[Gerry Gruber]

Rick..,

Thank you very much for your detailed advice. I will work through your suggestions and probably come back with more questions. One thing at the moment... you indicated that I need to let LILO know that I need scsi emulation. I am using LOADLIN instead (dual booting with WIN98SE). Is there a way to accomplish the same thing with LOADLIN, or do I need to set up my dual boot with LILO in order to get scsi emulation?

[rickenbacherus]

you indicated that I need to let LILO know that I need scsi emulation. I am using LOADLIN instead (dual booting with WIN98SE). Is there a way to accomplish the same thing with LOADLIN, or do I need to set up my dual boot with LILO in order to get scsi emulation?

Good question- sorry but I don't do windows. LILO can very easily be used for your dual boot though. Do cdrecord -scanbue and that should tell you if SCSI emulation is working because an IDE device wouldn't show up on the SCSI BUS otherwise right?

dmesg | less

will show you if SCSI emulation is being used as well.

[rickenbacherus]

you indicated that I need to let LILO know that I need scsi emulation. I am using LOADLIN instead (dual booting with WIN98SE). Is there a way to accomplish the same thing with LOADLIN, or do I need to set up my dual boot with LILO in order to get scsi emulation?

Good question- sorry but I don't do windows. LILO can very easily be used for your dual boot though. Do cdrecord -scanbus and that should tell you if SCSI emulation is working because an IDE device wouldn't show up on the SCSI BUS otherwise right?

dmesg | less

will show you if SCSI emulation is being used as well.

[Gerry Gruber]

Just to close the loop on this one, I have found out how to get linux to start scsi emulation using LOADLIN. It is simply a matter of adding the argument to the end of the loadlin command in the bat file. For example, my linux.bat file is now as follows:

@echo off
c:\loadlin c:\vmlinuz root=/dev/hdb4 ro hdc=ide-scsi

hdb4 is the partition that I wish to boot from, and hdc is the device (my dvd/cd-rw) for which I need scsi emulation. After booting linux in this way, if I try:

cdrecord -scanbus

I see that scsi emulation is indeed operating, and I now have software control over my cd-audio. Thanks again, Rickenbacherus for your assistance.

[rickenbacherus]

Glad you got it working but mostly thanks for taking the time to post your solution. Too many people forget to return and post their solution which does no one any good.