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2811 w/ vic2-2fxo callerid not working

Hi folks,

Im not able to get inbound callerid working with a 2811 and vic2-2fxo. Im using CME ver7.

I also have a 1751v with vic-2fxo-m1 that is working with callerid.

voice-port 0/0/0

connection plar opx 1001

caller-id enable


Re: 2811 w/ vic2-2fxo callerid not working

Caller-id can delivered differently by each carrier, I had a similiar issue and discovered that the telco was using polarity line reversal.

In this scernario, an FXO interface cannot detect line-reversal alerting in the on-hook state.

For this reason, DSPs must be pre-allocated to serve the Type 1 caller ID information when it arrives.

Preallocating the DSPs enables the DSP to continuously monitor for the arrival of caller-ID information.

Configure this command 'caller-id alerting

dsp-pre-alloc' on the FXO port when the incoming subscriber telephone line uses line polarity reversal to signal the start of caller-ID information transmission.

If you debug vpm signal, this should give you an indication in the debug if line-reversal is being used by your telco. Below is a debug example:-

If CLID enabled and line-reversal, the you should see a similar debug as follows:-

Oct 13 14:23:35.263 BST: htsp_process_event: [0/3/0, FXOLS_ONHOOK, E_DSP_SIG_011


Oct 13 14:23:35.263 BST: fxols_line_reversal_clid_wait. Line reversal alerting

Oct 13 14:23:36.375 BST: [0/3/0] htsp_dsm_feature_notify_cb returns 2 id=DSM_FEATURE_SM_CALLERID_RX

Oct 13 14:23:36.375 BST: htsp_process_event: [0/3/0, FXOLS_ONHOOK, E_HTSP_CALLER


Oct 13 14:23:37.031 BST: htsp_process_event: [0/3/0, FXOLS_ONHOOK, E_DSP_SIG_000


Oct 13 14:23:37.035 BST: htsp_timer - 125 msec

Oct 13 14:23:37.163 BST: htsp_process_event: [0/3/0, FXOLS_WAIT_RING_MIN, E_HTSP


Oct 13 14:23:37.163 BST: htsp_timer - 10000 msec

Oct 13 14:23:38.119 BST: htsp_process_event: [0/3/0, FXOLS_RINGING, E_DSP_SIG_01


Oct 13 14:23:38.119 BST: fxols_ringing_not

Oct 13 14:23:38.119 BST: htsp_timer_stop

Oct 13 14:23:38.119 BST: htsp_timer_stop3

Oct 13 14:23:38.119 BST: [0/3/0] htsp_stop_caller_id_rx. message length 29htsp_s


Oct 13 14:23:38.119 BST: [0/3/0] get_fxo_caller_id:Caller ID received. Message t

ype=128 length=29 checksum=63

Oct 13 14:23:38.119 BST: [0/3/0] get_fxo_caller_id calling num= calling name= calling time=10/13 14:23

Oct 13 14:23:38.123 BST: htsp_process_event: [0/3/0, FXOLS_WAIT_SETUP_ACK, E_HTS


Oct 13 14:23:38.123 BST: fxols_wait_setup_ack:



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