[asterisk-bugs] [DAHDI-linux 0013866]: TDM400P FXO when configured for alaw fails to dialout

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=13866 
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Reported By:                alecdavis
Assigned To:                
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Project:                    DAHDI-linux
Issue ID:                   13866
Category:                   Core/Channels
Reproducibility:            always
Severity:                   block
Priority:                   normal
Status:                     new
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Date Submitted:             2008-11-09 19:44 CST
Last Modified:              2008-11-13 02:52 CST
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Summary:                    TDM400P FXO when configured for alaw fails to
dialout
Description: 
In /etc/dahdi/system.conf selecting alaw=35 causes the FXO to fail
dialout.

All that is heard is constant ~1000Hz square wave, this estimated.

Using mulaw=35 the line works fine.

This is not new, also happens on our production box which is Asterisk
1.6.0-rc6 with DAHDI-2.0.0-rc2
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---------------------------------------------------------------------- 
 (0094841) alecdavis (reporter) - 2008-11-13 02:52
 http://bugs.digium.com/view.php?id=13866#c94841 
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User configuration issue, but console indications of 'Default law: alaw'
appears incorrect in the misconfigured senario.

file /etc/modprode.d/dahdi requires the following line
'options wctdm alawoverride=1'

Setting alaw=35 /etc/dahdi/system.conf then seemed to make no difference.

Both console outputs below indicate "Default law: alaw"

================================================
CONSOLE output below with correct working alaw configuration:
'options wctdm alawoverride=1' in /etc/modprode.d/dahdi 
================================================

Asterisk*CLI> dahdi show channel 35
Channel: 35I>
File Descriptor: 47
Span: 2
Extension:
Dialing: no
Context: auckland-el
Caller ID:
Calling TON: 0
Caller ID name:
Mailbox: none
Destroy: 0
InAlarm: 0
Signalling Type: FXS Loopstart
Radio: 0
Owner: <None>
Real: <None>
Callwait: <None>
Threeway: <None>
Confno: -1
Propagated Conference: -1
Real in conference: 0
DSP: no
Busy Detection: no
TDD: no
Relax DTMF: no
Dialing/CallwaitCAS: 0/0
Default law: alaw
Fax Handled: no
Pulse phone: no
DND: no
Echo Cancellation:
        128 taps
        currently OFF
Actual Confinfo: Num/0, Mode/0x0000
Actual Confmute: No
Hookstate (FXS only): Onhook
Asterisk*CLI>

================================================
CONSOLE Output below with incorrect alaw configuration
'alaw=35' in /etc/dahdi/system.conf 
'options wctdm alawoverride=1' missing /etc/modprode.d/dahdi 
================================================

Asterisk*CLI> dahdi show channel 35
Channel: 35I>
File Descriptor: 47
Span: 2
Extension:
Dialing: no
Context: auckland-el
Caller ID:
Calling TON: 0
Caller ID name:
Mailbox: none
Destroy: 0
InAlarm: 0
Signalling Type: FXS Loopstart
Radio: 0
Owner: <None>
Real: <None>
Callwait: <None>
Threeway: <None>
Confno: -1
Propagated Conference: -1
Real in conference: 0
DSP: no
Busy Detection: no
TDD: no
Relax DTMF: no
Dialing/CallwaitCAS: 0/0
Default law: alaw
Fax Handled: no
Pulse phone: no
DND: no
Echo Cancellation:
        128 taps
        currently OFF
Actual Confinfo: Num/0, Mode/0x0000
Actual Confmute: No
Hookstate (FXS only): Onhook
Asterisk*CLI> 

Issue History 
Date Modified    Username       Field                    Change               
====================================================================== 
2008-11-13 02:52 alecdavis      Note Added: 0094841                          
======================================================================