BS11Troubleshooting » History » Revision 14
Revision 13 (dexter, 02/19/2016 10:47 PM) → Revision 14/23 (dexter, 02/19/2016 10:47 PM)
= Troubleshooting = == Known problems with the LMT connection == Problem: 'bs11_config' can't get a connection to the BS-11 (no 'LMT LOGON: ACK') Solution: The BS-11 is a little bit choosy about the RS232 levels, I discovered some problems with my Dell PC (could receive anything, but no tx). Just switch to an el-cheapo USB to Serial adapter, this should solve the problem. Some background notes: We measured the RS232 levels and we found out that the level of our RS232<==>USB Adaptor is much lower (about +/-6 Volts) than normaly expected (+/-12V). The BS11 transmits at a semeliar level (about +/-8 Volts). This may be an explaination why the BS11 does not like the normal (+/-12V) levels. [[Image(Lmt_bts-rx.jpg, 15%)]] [[Image(Lmt_bts-tx.jpg, 15%)]] [[Image(Lmt_btx_tx_does_not_work.jpg, 15%)]] From left to right: BTS-RX (PC-TX), BTS-TX (PC-RX), BTS-RX (PC-TX) with a real RS232 port. == The "everything looks good - nothing works" - problem == When you use openBSC with early mISDN drivers (<= 2.6.31, patched) your setup might refuse to work while everything looks normal. No error messages, normal PLL Work Value Abis Link works perfect but no phone can see your network. Than the first thing you should do is to upgrade your kernel to get the latest mISDN drivers. Note: When your BS11 is out of Sync the setup also refuses to work. In this case you sould sync your BS11 as described in the isdnsync-howto. See also: http://lists.gnumonks.org/pipermail/openbsc/2009-August/000783.html
