[asterisk-bugs] [Asterisk 0018474]: [patch] "Caller*ID failed checksum" on Wildcard TDM2400P and TDM410

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
====================================================================== 
https://issues.asterisk.org/view.php?id=18474 
====================================================================== 
Reported By:                nivek
Assigned To:                rmudgett
====================================================================== 
Project:                    Asterisk
Issue ID:                   18474
Category:                   Channels/chan_dahdi
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     feedback
Asterisk Version:           1.8.1 
JIRA:                       SWP-2751 
Regression:                 No 
Reviewboard Link:            
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Request Review:              
====================================================================== 
Date Submitted:             2010-12-14 16:12 CST
Last Modified:              2011-03-14 11:38 CDT
====================================================================== 
Summary:                    [patch] "Caller*ID failed checksum" on Wildcard
TDM2400P and TDM410
Description: 
Receiving message "Caller*ID failed checksum" on every call.  Changing
"cidrw_gain" did nothing.  Other cid-based parameters did nothing.
Tested line using a analog phone with the Caller ID feature and received
caller id.

====================================================================== 

---------------------------------------------------------------------- 
 (0132908) svnbot (reporter) - 2011-03-14 11:38
 https://issues.asterisk.org/view.php?id=18474#c132908 
---------------------------------------------------------------------- 
Repository: asterisk
Revision: 310633

U   branches/1.4/main/callerid.c

------------------------------------------------------------------------
r310633 | rmudgett | 2011-03-14 11:38:25 -0500 (Mon, 14 Mar 2011) | 25
lines

"Caller*ID failed checksum" on Wildcard TDM2400P and TDM410

The last character in the caller id message is getting a framing error.

The checksum is the last character in the message.  A framing error in the
checksum could be because:
1) The sender did not send a full stop bit.
2) The sender cut off the FSK carrier too soon.
3) The sender opted to send zero of the specified zero to 10 trailing mark
bits and round-off errors in the code resulted in the code not being where
it thought it was in the demodulated bit stream.

Bit 8 of 'b' is set when parity error.
Bit 9 of 'b' is set when framing error.

Made ignore the framing and parity error bits if the errored character is
the checksum.  We can tolerate a framing/parity error there.  The checksum
character validates the message.

(closes issue https://issues.asterisk.org/view.php?id=18474)
Reported by: nivek
Patches:
      callerid.c.1.patch uploaded by nivek (license 636) (with
modifications)
Tested by: nivek

------------------------------------------------------------------------

http://svn.digium.com/view/asterisk?view=rev&revision=310633 

Issue History 
Date Modified    Username       Field                    Change               
====================================================================== 
2011-03-14 11:38 svnbot         Note Added: 0132908                          
======================================================================