- baseband-devel - lists.osmocom.org

re: Clock from phone
by Dario Lombardo 03 Jul '12

03 Jul '12

On Tue, Jul 3, 2012 at 3:27 PM, Alexander Huemer <alexander.huemer(a)xx.vu> wrote: > On Tue, Jul 03, 2012 at 03:08:02PM +0200, Dario Lombardo wrote: >> On Tue, Jul 3, 2012 at 1:44 PM, Sylvain Munaut <246tnt(a)gmail.com> wrote: >> >> In some past post of the ML, I've read that someone was trying to get >> >> the GSM 10MHz clock reference from the motorola phones. >> >> This aimed at feeding usrp with a stable reference, if I'm not wrong. >> >> Anything new this side? This would be extremely useful if GPS signal >> >> can't be got but GSM cell can. >> > >> > 1) It's not 10 MHz but 26 MHz >> >> Mmm... but the front panel of usrp is fed by 10 MHz/1pps... isn't it? >> > There are different revisions of the USRP. Sylvain is talking about the > USRP1, you of a later rev. > The USRP1 has an (unpopulated) direct clock input. > The other USRP revisions have a reference clock input, which is > something different. > You are definitly right. I was taling about N210, which can be fed by reference clock input. >> > 2) Yes it works, but you can't feed the USRP directly, you need to >> > multiply it by 2 (using a PLL chip) to get 52 MHz for the USRP. >> >> Can you provide some link to read something about it? >> > See [1,2,3] >> Don't you think that this way could be much more preferrable than the >> GPS way, if USRP is under GSM coverage? I mean: the clock from GSM is >> next to us... why just don't use it? Probably there's something I'm >> missing, since this approach is much less used than GPS clocking... >> > > There are many ways to provide a stable reference clock. A OCXO (e.g. > [4]), a cheap rubidium standard, the clock tamer[5], ... > Every option has up and downsides. > Just the "pirelli" way uses clock from existing GSM network. As said before I think that "reusing" the clock from network could be very useful, but I don't know if it is more difficult than generate the signal itself. Is that possible using motorola phones? Did anyone investigate that possibility?

1 0

Clock from phone
by Dario Lombardo 03 Jul '12

03 Jul '12

In some past post of the ML, I've read that someone was trying to get the GSM 10MHz clock reference from the motorola phones. This aimed at feeding usrp with a stable reference, if I'm not wrong. Anything new this side? This would be extremely useful if GPS signal can't be got but GSM cell can. Dario.

3 3

little confusion while studying l1l2 interface via sercomm
by Akib Sayyed 03 Jul '12

03 Jul '12

in layer23 apps we open local unix socket in layer23 app and one in osmocon another socket to communicate in between. now in layer23 we just send (write) or receive (read) msg. but we handle actual communication with phone is handled in osmocon. now flow of functions is main ->register_tool_server->tool_accept->un_tool_read->hdlc_send_to_phone->sercomm_sendmsg then sercomm handles all transmission in details then layer1 accept all data via so i wanted to ask that how does rssi firmware is sending data directly to l1 -l2 and i would also like to ask what is actual protocol used in communication between l1 and l2 -- Akib Sayyed Matrix-Shell akibsayyed(a)gmail.com akibsayyed(a)matrixshell.com Mob:- +91-966-514-2243

2 1

help on sim.c
by Gabriele.rago 02 Jul '12

02 Jul '12

Hello all, I am using osmocomm (branch sylvain) on a motorola C140. I have uncommented the line "#define DEBUG" on src/target/firmware/calypso/sim.c and recompiled. I have connected an interface between my PC and phone sim slot ( a pl2303 usb module, with a diode between TXD and RXD and a 22K resistor between +5V and RXD). Now I have opened the serial port on my PC with these settings: baud rate = 9600 databits = 8 parity = even stopbits = 2 and I am sending the byte "3B" to the phone, but I see in osmocon console: "SIM-ISR:  Waiting for read (9B)..." (id est the phone seems like to receive "9B" instead of "3B"), where I am wrong?

1 0

Trying to understand talloc.h
by Akib Sayyed 30 Jun '12

30 Jun '12

i am trying to understand talloc* functions. in layer23 app. i want to know what exact role they perform in these apps. its ok about allocating memory and freeing them but logically why they are used. -- Akib Sayyed Matrix-Shell akibsayyed(a)gmail.com akibsayyed(a)matrixshell.com Mob:- +91-966-514-2243

2 1

TOMORROW: Jun 27, 8pm / Osmocom meeting in Berlin
by Holger Hans Peter Freyther 26 Jun '12

26 Jun '12

Hi all! This is the announcement for the next Osmocom Berlin meeting. Jun 27, 8pm @ CCC Berlin, Marienstr. 11, 10113 Berlin Nico will talk about SAP (SIM Access Profile) in osmocomBB. If you are interested to show up, feel free to do so. There is no registration required. The meeting is free as in "free beer", despite no actual free beer being around. Updates and the blog post can be found here[1]. Regards, Holger [1] http://openbsc.osmocom.org/trac/blog/osmug-20120627

1 0

the building of /src/shared/libosmocore
by bob wisebob 26 Jun '12

26 Jun '12

3 3

Need guidance for layer1 and layer 2 connection in firmware
by Akib Sayyed 26 Jun '12

26 Jun '12

i am trying to port mobile app on phone it self as a firmware but unable to find out how exactly L1 on phone communicate with L2 L3 on pc. please help me with that. -- Akib Sayyed Matrix-Shell akibsayyed(a)gmail.com akibsayyed(a)matrixshell.com Mob:- +91-966-514-2243

1 0

LCD is going off after custom RSSI loading
by Akib Sayyed 23 Jun '12

23 Jun '12

i have been trying to load RSSI and run it. all went well. but after all of sudden LCD went off tried to debug but didnt understand much. here is log OSMOCOM Loader (revision osmocon_v0.0.0-1347-g4f0acac) ====================================================================== Running on compal_e88 in environment compalram Found flash of 2097152 bytes at 0x0 with 2 regions fb_td014_init: initializing LCD. //after above msg LCD is going off and firmware is giving output correct as it was giving before then i created custom program kept only board_init(); then compiled and uploaded in phone and started but still same issue. then fetched fresh git and tried to compile then also same issue. steps taken to compile test.c created folder test in target/firmware/apps/ added test in make file application list renamed test.c to main.c steps taken to load code in c118 ./host/osmocon/osmoload memload 0x820000 ./target/firmware/board/compal_e86/test.highram.bin ./host/osmocon/osmoload jump 0x820000 please help me with that -- Akib Sayyed Matrix-Shell akibsayyed(a)gmail.com akibsayyed(a)matrixshell.com Mob:- +91-966-514-2243

2 2

osmocon idling with C155 when using bus pirate
by Ian Kinsey 21 Jun '12

21 Jun '12

A Motorola C155 is hooked up to my computer via a bus pirate as per the official instructions, everything is properly wired and the phone seems to work. However, Osmocon neither indicates the presence of any data being sent or received when attempting to communicate with the phone; it just idles. Is there any extra logic in the cable? Any help would be appreciated.

2 1