Sound Problem with CM8738

[David Rush]

Jeffrey:

Good thinking.  But I checked things out, and could not find any obvious 
conflicts.

My system only has one of the apparent two (based upon the BIOS setup) 
on-board serial ports enabled, and dmesg agrees:

Detected PS/2 Mouse Port.
Serial driver version 4.27 with MANY_PORTS MULTIPORT SHARE_IRQ enabled
ttyS00 at 0x03f8 (irq = 4) is a 16550A
pty: 256 Unix98 ptys configured
apm: BIOS version 1.2 Flags 0x07 (Driver version 1.9)

When I boot W98, the system indicates that IRQ 3 is shared with the USB 
port (which is not supported with my 2.2 kernel, I understand), yet sound 
works fine.  Perhaps without USB supported, the IRQ-sharing doesn't work 
right?  IIRC, I may be able to disable USB in the BIOS - not a great end 
solution, but useful for troubleshooting and OK for the moment.

I/O space looks good (no conflicts found) according to W98.  My network 
"adapter" (an on-board thingy as well) lives in space below cc00 (uses the 
"dmfe" module, whatever the heck that is).

I could find nothing in the BIOS setup or with the W98 driver binaries that 
allows me to change the settings that my on-board sound hardware 
use.  Drats - it appears I can't even experiment with that.

IRQ 5 is unused in my system.

The only "modem" in my system is a Lucent "Win Modem", which is ignored by 
Linux (and resources don't appear to conflict with anything).

David

At 10/7/01 03:18 PM -0500, Jeffrey A. McCright wrote:
>On Friday 05 October 2001 13:47, David Rush wrote:
> > Hi. I've been running RH 6.2 for quite a while on my 450 MHz P-III with
> > 64 MB, but I've never had sound working acceptably.  I've got an Intel
><snip>
> >
> > dmesg says:
> > cm: version v1.1 time 21:09:15 Mar 7 2000
> > cm: found CM8738 adapter at io 0xcc00 irq 3
>
>David,
>
>Based on the information you listed from dmesg, It appears your sound card is
>using interupt 3 and Base memory at cc00. The base Memory address listed
>falls directly in a commonly used memory range for Network adaters. This may
>or may not be an issue as Network cards can be found at adresses of c000 to
>dd00, and even into the E000 area.
>
>It would probably be best to move the sound card to IRQ5 which is the legasy
>IRQ for sound cards. My reasoning for this is that your system probably has 2
>Serial ports and posibly a modem. In Pre Plug-N-Play times, Serial ports 1 &
>3 referred to as COM1 and COM3 shared IRQ 4 while Serial Ports 2 & 4 referred
>to as COM2 and COM4 shared IRQ3. If you have 2 serial ports, it is most
>likely that at least one of them is using IRQ 3 thus causing a resource
>conflict. If you have an internal modem, then this can further complicate the
>issue as it will provide it's own Serial Port, placing itself usually on IRQ
>3 or 4. With the introduction of Plug-N-Play (PNP) IRQs and Base I/O
>Addresses and Base Memory Addresses are now up for grabs. Modems can find
>themselves on virtually any of the non-reserved IRQs, etc...
>
>Long disertation to basically explain that you could simply disable your
>second Serial port in CMOS and remove any modems to see if the issue resolves
>itself. Ultimately, you will want to move the Sound card to IRQ 5. This may
>be possible thru the CMOS setup utility burned into your BIOS or by using the
>driver/utility disk that came with your system/system board.
>
>I hope this helps.
>
>Thanks,
>
>Jeffrey A. McCright