[Asterisk-Users] DTMF Detection and noise in TDM10B

[Scott Lambert]

On Tue, Jun 10, 2003 at 07:08:45PM +0200, Sergio Serrano Revuelto wrote:
> HI all,
> 	we get a TDM10B to probe it. I find two problems:
> 	
> 	-First, I hear a lot of noise in communication. I have tried do
> "dd if=/dev/zero of=/dev/null &" but it isn't work.
> 	-Second, When I pickup phone connected to TDM10B I hear a
> strange dial tone and * doesn't detect DTMF.

That is the same problem I had last week.  The system had worked before then 
started with that nonsense.  I swapped PCI slots for the TDM and X100P cards.
That made it so the TDM card had its own IRQ and the X100P was sharing with 
the AC97 sound device on the motherboard, which is unused.  That fixed my 
symptoms.

These cards definately have problems with IRQ sharing, which isn't
supposed to happen on a PCI bus.  My laptop manages to run flawlessly
with every PCI device, except graphics and IDE controller, on the same
IRQ.  That includes 802.11b PCMCIA card, compact flash reader, sound
device, Intel EEPro, Lucent Winmodem, and some other thing.

Back in the OS/2 days I was even able to share IRQs with multiple ISA
based serial ports using the SIO.SYS driver.  Never dropped a bit.

-- 
Scott Lambert                    KC5MLE                       Unix SysAdmin
lambert at lambertfam.org