cell_log + gsmmap = KML without positions

Matthias Meisser digi_c at arcor.de
Mon Apr 22 09:18:43 UTC 2013


Hi list,

sorry for abusing the list for a somewhat support request but 
unfortunatly I didn't got answers in the IRC.

I'm interested to use BB for some experiments on mapping GSM cells 
(opencellid.org and similar).
So I finally got cell_log to work and my general BB setup works fine 
here on my laptop. But even with a working GPS, I don't get any 
positions in the osmocom logfile or the resulting kml by gsmap. Here is 
what I do:

I pair my Bluetooth GPS via
sudo rfcomm connect /dev/rfcomm0 00:AA:BB:CC:DD:EE
I test it via
sudo cat /dev/rfcomm0
and it prints the usual NMEA stuff

I connect my mobile C123 and fire up osmocon  with L23:
sudo ./osmocon -p /dev/ttyUSB0 -m c123xor 
'/home/matthias/opencellid/osmocom-bb/src/target/firmware/board/compal_e88/layer1.compalram.bin' 


After upload I start cell_log
sudo ./cell_log -f /dev/rfcomm0
which looks ok:
<0010> app_cell_log.c:216 Using GPS serial device /dev/rfcomm0
Failed to connect to '/tmp/osmocom_sap'.
Failed during sap_open(), no SIM reader
<000e> cell_log.c:804 Scanner initialized
Mobile initialized, please start phone now!
<000e> cell_log.c:368 Measure from 0 to 124
<000e> cell_log.c:368 Measure from 512 to 885
<000e> cell_log.c:368 Measure from 955 to 1023
<000e> cell_log.c:359 Measurement done
<000e> cell_log.c:341 Sync ARFCN 17 (rxlev -59, 421 syncs left)
<000e> cell_log.c:341 Sync ARFCN 675 (rxlev -62, 420 syncs left)
<000e> cell_log.c:341 Sync ARFCN 85 (rxlev -65, 419 syncs left)
<000e> cell_log.c:191 Cell: ARFCN=85 MCC=262 MNC=01 (Germany, T-Mobile)
<000e> cell_log.c:341 Sync ARFCN 47 (rxlev -66, 418 syncs left)
<000e> cell_log.c:191 Cell: ARFCN=47 MCC=262 MNC=01 (Germany, T-Mobile)
<000e> cell_log.c:341 Sync ARFCN 6 (rxlev -73, 417 syncs left)
<000e> cell_log.c:191 Cell: ARFCN=6 MCC=262 MNC=02 (Germany, Vodafone)
<000e> cell_log.c:341 Sync ARFCN 75 (rxlev -73, 416 syncs left)
<000e> cell_log.c:191 Cell: ARFCN=75 MCC=262 MNC=02 (Germany, Vodafone)
<000e> cell_log.c:341 Sync ARFCN 671 (rxlev -73, 415 syncs left)
<000e> cell_log.c:341 Sync ARFCN 22 (rxlev -75, 414 syncs left)
<000e> cell_log.c:341 Sync ARFCN 25 (rxlev -75, 413 syncs left)
<000e> cell_log.c:341 Sync ARFCN 20 (rxlev -77, 412 syncs left)
<000e> cell_log.c:341 Sync ARFCN 90 (rxlev -78, 411 syncs left)

But it doesn't write any positions at the logfile nor shows that it got 
a working GPS position. Only at a few starts I saw this line coming up:
<000e> cell_log.c:804 Scanner initialized
Mobile initialized, please start phone now!
NMEA checksum error
So I tried to set the baud rate but this message doesn't seem to be 
reproducable.

Is there anything else I can do, or might it be some kind of software 
bug for my specific setup?

cya,
Matthias







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