OsmocomBB

Since recently I noticed that the modem app ignores the ARFCN value passed via as a command line argument (-a/--arfcn).

fixeria@DELL:~/projects/osmocom/bb/src/host/layer23$ ./src/modem/modem -a 1 -d DL1C
Copyright (C) 2022 by sysmocom - s.m.f.c. GmbH <info@sysmocom.de>

License GPLv2+: GNU GPL version 2 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

DL1C INFO l1ctl.c:776 Tx Reset Req (1)
DL1C DEBUG l1l2_interface.c:139 Sending: '0d 00 00 00 01 00 00 00 '
DL1C INFO l1ctl.c:786 Layer1 Reset indication
DL1C INFO l1ctl.c:427 Sync Req
DL1C DEBUG l1l2_interface.c:139 Sending: '01 00 00 00 03 67 00 64 27 10 03 20 03 07 00 00 19 '
DL1C INFO l1ctl.c:161 snr=0000, arfcn=871 result=255
DL1C ERROR l1ctl.c:165 FBSB RESP: result=255

This is unfortunately also the case for misc apps like ccch_scan and cbch_sniff.

fixeria@DELL:~/projects/osmocom/bb/src/host/layer23$ ./src/misc/ccch_scan -a 1 -d DL1C
Copyright (C) 2010 Harald Welte <laforge@gnumonks.org>
Contributions by Holger Hans Peter Freyther

License GPLv2+: GNU GPL version 2 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

DL1C INFO l1ctl.c:776 Tx Reset Req (1)
DL1C DEBUG l1l2_interface.c:139 Sending: '0d 00 00 00 01 00 00 00 '
DL1C INFO l1ctl.c:786 Layer1 Reset indication
DL1C INFO l1ctl.c:427 Sync Req
DL1C DEBUG l1l2_interface.c:139 Sending: '01 00 00 00 03 67 00 64 27 10 03 20 03 07 00 00 19 '
DL1C INFO l1ctl.c:161 snr=0000, arfcn=871 result=255
DL1C ERROR l1ctl.c:165 FBSB RESP: result=255

As can be seen, the apps are using hard-coded arfcn=871 regardless of the requested ARFCN.