layer 1 debugging

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Andreas.Eversberg Andreas.Eversberg at versatel.de
Mon Jun 1 18:09:56 UTC 2009


hi,
 
i added layer 1 state change (and initial state) reporting to mISDN
kernel driver. this is usefull to resolve E1 connection problem.
 
1. download the latest mISDN driver from www.mISDN.org using git:
 
 git-clone git://git.misdn.org/git/mISDN.git/

change to socket branch:
 
 cd mISDN
./checkout-branch.sh socket
 
compile and install as usual
 
 make force # remove kernel mISDN includes
 make
 make install
 
load mISDN as usual.
 
 
2. run bsc_hack using debug option: --debug=DMI
 
Allowing everyone?
DB: Database initialized.
DB: Database prepared.
1 devices found
        id:             0
        Dprotocols:     00000018
        Bprotocols:     0000006e
        protocol:       4
        nrbchan:        30
        name:           hfc-e1.1
activate bchan
activate bchan
Mon Jun  1 18:51:43 2009 <1000> input/misdn.c:124 alen =6, dev(9)
channel(0) sapi(63) tei(127)
Mon Jun  1 18:51:43 2009 <1000> input/misdn.c:127 <= len = 12, prim(0x8)
id(0x7f3f): DL_INFORMATION_IND
Mon Jun  1 18:51:43 2009 <1000> input/misdn.c:134 DL_INFORMATION_IND:
use channel(0) sapi(63) tei(127) for now
mISDN message for unknown sign_link
Mon Jun  1 18:51:43 2009 <1000> input/misdn.c:124 alen =6, dev(9)
channel(0) sapi(63) tei(127)
Mon Jun  1 18:51:43 2009 <1000> input/misdn.c:127 <= len = 8,
prim(0x102) id(0x7f3f): PH_ACTIVATE_IND
Mon Jun  1 18:51:43 2009 <1000> input/misdn.c:161 PH_ACTIVATE_IND:
channel(0) sapi(63) tei(127)
 
in this case we see "PH_ACTIVATE_IND", because BS11 is connected and
sending a signal.
 
 
3. check your card: (most common type)
 
close to the plug there are two jumpers. the are used to select between
1,2,4,5 and 1,2,3,6 pin selection. be sure they are to the left for
standard 1,2,4,5 pinning.
 
take an rj45 plug and connect pin 1 with 4 and 2 with 5. start bsc_hack
and plug it into your card. you should see "PH_ACTIVATE_IND" when you
plug it. your card is working.
 
if nothing works, check your termination switches. refer to the card's
manual. the must be set to 120 ohms, if the termination jumpers on your
BS11 are pulled out. without termination, the card might not work.
 
 
4. check your BS11
 
remove the plug and connect the cable to the BS11: one pair (pin 1 and
2) to Y01 and one pair (pin 4 and 5) to Y02. after bootup ob BS11 you
will see "PH_ACTIVATE_IND" if you connect both paris in the correct
order. you must connect both pairs because BS11 will only send a signal,
if it receives a signal. pin 1 can be wapped with pin 2, pin 4 with pin
5 also. the E1 interface does not care about that.
 
 
5. check data link connection:
 
you have already received the management process via
"DL_INFORMATION_IND" on sapi 63 tei 127. if BS11 software load is
running, you will receive additional data links from BS11:
 
- sapi 62 tei 25
- sapi 0 tei 25
- sapi 0 tei 1
 
these are three datalinks. each one is created and sends us
"DL_INFORMATION_IND" on creation, "DL_ESTABLISH_IND" on activation and
"DL_DATA_IND" when receiving data on that link.
 
 
hope that helps.
 
andreas
 
 
 


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