Connecting an ISDN telephone

hello, rcashell:
have you check the jumper for NT mode and power supply on the card? mISDN has a tool for debugging, you can try that.
Regards!
James.zhu

Hi James,

thank you for the tip. I have a quick question about my possible configuration. If I am connecting a phone directly into the openvox card do I need a cross over cable for this or is a regular RJ45 sufficient?

I tried the ISDN debug tool but it is not giving any output so I can only guess that the problem is somewhere with my hardware setup.

Hi James,

I have another question, the card has been set to NT mode with power enabled and power cable added. However, after reading some literature (and this is where it is confusing) should I configure the adapter in mISDN.conf as TE or NT?

hello, Rcashell:
You use RJ45 connector to connect with your ISDN phone. there are two files you have to edit. mISDN.conf and misdn.conf. the two files work as zaptel.conf and zapata.conf. please check the mISDN.conf under /etc, set it as NT mode, if the port connects with ISDN phone. otherwise, if it is TE mode. you also need to check the /etc/asterisk/misdn.conf as well, make sure context can match the context in extensions.conf . good luck!
James.zhu

I have made some inroads with this but I still cannot get this to work. I have configured the mISDN.conf configuration file indicating that the ports should be nt_ptp. I start the mISDN processes and when I enable the mISDNdebugtool I see some output when I pick up the handset.

# mISDNdebugtool -v
Received packet from 127.0.0.1:33264 (vers:1 protocol:NT type:D_RX id:00000100 plen:
1199882616.814256000: fc ff 03 0f 93 c4 01 ff

Received packet from 127.0.0.1:33264 (vers:1 protocol:NT type:D_RX id:00000100 plen:
1199882618.862256000: fc ff 03 0f 0e c9 01 ff

Received packet from 127.0.0.1:33264 (vers:1 protocol:NT type:D_RX id:00000100 plen:
1199882620.894256000: fc ff 03 0f 89 ce 01 ff

This appears to be working fine. Then I start asterisk and when I pick up the receiver I get no dial tone. When I issue misdn show stacks I get the following output:

CLI> misdn show stacks
BEGIN STACK_LIST:
* Port 1 Type NT Prot. PTP L2Link DOWN L1Link:UP Blocked:0 Debug:4
* Port 2 Type NT Prot. PTP L2Link DOWN L1Link:DOWN Blocked:0 Debug:4
* Port 3 Type NT Prot. PTP L2Link DOWN L1Link:DOWN Blocked:0 Debug:4
* Port 4 Type NT Prot. PTP L2Link DOWN L1Link:DOWN Blocked:0 Debug:4

For some reason the L1Link is up but the L2Link remains down. I have read lots in the last week on this but I cannot find any good articles that explain in detail ISDN and its configuration. Can anyone help me with both finding good articles on the subject of ISDN and also on helping me resolve this issue?

Many thanks

hello, friend:
if you set the port in NT modes, which can connect with ISDN phone, but no incoming and outgoing line. if you want to make a outbound calls with ISDNｐｈｏｎｅ，　ａｔ　ｌｅａｓｔ　one port should be TE and one port should be NT mode. the TE port connects with ISDN line. i think user manual has explained it. please read it. or you can go to asteriskguru.com and voip-info.org to find resource. it is sufficient for your case.
Regards,
James.zhu