How to disable polarity reversal detection on dahdi?


#1

Hello
I have problem with one PSTN line on asterisk - there is a fire alarm system connected on that line before PBX. Every 5 minutes that device makes some checks and switches polarity on line, so Asterisk see polarity reversal events and answers on non-existing calls.
Asterisk debug:

[2011-08-19 01:38:57.435] DEBUG[4455]: chan_dahdi.c:10183 do_monitor: Monitor doohicky got event Polarity Reversal on channel 4 [2011-08-19 01:38:58.323] DEBUG[4455]: chan_dahdi.c:10183 do_monitor: Monitor doohicky got event Polarity Reversal on channel 4 [2011-08-19 01:39:00.904] DEBUG[4455]: chan_dahdi.c:10183 do_monitor: Monitor doohicky got event Polarity Reversal on channel 4 [2011-08-19 01:39:01.428] DEBUG[4455]: chan_dahdi.c:10183 do_monitor: Monitor doohicky got event Polarity Reversal on channel 4 [2011-08-19 01:39:01.707] DEBUG[4455]: chan_dahdi.c:10183 do_monitor: Monitor doohicky got event Ring Begin on channel 4 [2011-08-19 01:39:01.717] DEBUG[4455]: chan_dahdi.c:10183 do_monitor: Monitor doohicky got event Polarity Reversal on channel 4 [2011-08-19 01:39:01.862] DEBUG[4455]: chan_dahdi.c:10183 do_monitor: Monitor doohicky got event Polarity Reversal on channel 4 [2011-08-19 01:39:02.168] DEBUG[4455]: chan_dahdi.c:10183 do_monitor: Monitor doohicky got event Ring/Answered on channel 4 [2011-08-19 01:39:02.168] DEBUG[4455]: dsp.c:479 ast_tone_detect_init: Setup tone 1100 Hz, 500 ms, block_size=160, hits_required=21 [2011-08-19 01:39:02.168] DEBUG[4455]: dsp.c:479 ast_tone_detect_init: Setup tone 2100 Hz, 2600 ms, block_size=160, hits_required=116 [2011-08-19 01:39:02.168] DEBUG[4455]: dsp.c:1596 ast_dsp_set_busy_pattern: dsp busy pattern set to 0,0 [2011-08-19 01:39:02.168] DEBUG[4455]: devicestate.c:442 devstate_event: device 'DAHDI/4-1' state '2' -- Starting simple switch on 'DAHDI/4-1'

When real call incoming debug looks so:

[2011-08-19 01:40:30.945] DEBUG[4455]: chan_dahdi.c:10183 do_monitor: Monitor doohicky got event Ring Begin on channel 1 [2011-08-19 01:40:31.831] DEBUG[4455]: chan_dahdi.c:10183 do_monitor: Monitor doohicky got event Ring/Answered on channel 1 [2011-08-19 01:40:31.831] DEBUG[4455]: dsp.c:479 ast_tone_detect_init: Setup tone 1100 Hz, 500 ms, block_size=160, hits_required=21 [2011-08-19 01:40:31.831] DEBUG[4455]: dsp.c:479 ast_tone_detect_init: Setup tone 2100 Hz, 2600 ms, block_size=160, hits_required=116 [2011-08-19 01:40:31.831] DEBUG[4455]: dsp.c:1596 ast_dsp_set_busy_pattern: dsp busy pattern set to 0,0 [2011-08-19 01:40:31.831] DEBUG[4455]: devicestate.c:442 devstate_event: device 'DAHDI/1-1' state '2' -- Starting simple switch on 'DAHDI/1-1'

'cause our provider doesn’t use polarity switching is it possible to disable in asterisk polarity reversal detection or ring answer on that event?

My hw&sw:
Asterisk 1.6.2.20
DAHDI Version: 2.5.0
wctdm24xxp+ Wildcard TDM800P