Hi,
I've hacked something together to quickly test non-combined CCCH.
However, I've hit a problem when trying to receive anything on another
timeslot than 0.
The TX side seems to work fine as the BTS can see my location update
request and answers with a reject, but on the MS side, I never see the
reject and wireshark only shows invalid incohrent data on the RX.
The frames for SDCCH/8 show really nothing valid (looks like random
bytes), things like
09 80 7f 47 49 06 1d 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
09 00 47 d5 2d 06 1e 00 00 69 7c a0 91 3d 22 ff ab fe 6c 4f 56 4f 36
...
while the frames for the associated SAACH show at least something gsm-like :
03 03 01 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b
but that's not quite a SI5/6 ...
To RX/TX on TS=1, I just delayed the RX/TX window by 625 bits (4 *
156.25) when I'm in dedicated channel mode by chaning the 'start' in
l1s_tx_win_ctrl / l1s_rx_win_ctrl
Is there something else that should be done ?
Cheers,
Sylvain
Hi!
Recently we've had the idea of using OsmocomBB with a simple firmware
that synchronizes to an existing GSM networks FCCH and use the resulting
13MHz clock to drive the USRP for airprobe or OpenBTS.
Ideally, we would even use the Calypso-internal PLL (for ARM or DSP) to
multiply it up to the required 52 MHz. However, neither the Openmoko
nor the Compal/Motorola phones expose any of the 3 clock output pads :(
So the only choice is to use something along the lines of the
http://focus.ti.com/docs/prod/folders/print/cdcvf25084.html
as a quad clock multiplier and attach it to the CLK13OUT signal of the
phone.
The chip is available for 9 USD in single quantities at digikey, and
possibly cheaper at other sources. Combined with a sub-20EUR phone it
might be a very cheap but still accurate frequency source for OpenBTS -
at least as long as there are any commercial gsm networks available.
Regards,
Harald
--
- Harald Welte <laforge(a)gnumonks.org> http://laforge.gnumonks.org/
============================================================================
"Privacy in residential applications is a desirable marketing option."
(ETSI EN 300 175-7 Ch. A6)
Hi All!
That's true, I managed to run U-Boot on MT6235, but linux kernel is
not fully functional yet (it's fresh stuff as I managed to ran it on
Tuesday and then I was off to conference).
For MT6235 development I chose Sciphone G2, which is pretty cheap.
After some time I managed to download code to SRAM (just 64KB) using
MTK's FlashTool.
MTK FlashTool communicates over UART directly with MT6235 bootloader
and sends its own chunk of code (about 58KB) which is executed in SRAM
and communicates with FlashTool.
I found on pudn.com some pack to customize code loaded by FlashTool,
thanks to which I could download my own code to SRAM (without JTAG).
The problem was that it had to be linked with some security libraries
which occupied about 56KB and not much memory left for my own code.
Then I decided to try find JTAG pins to get all control on MT6235.
That took me sometime, but finally I succeeded.
The other bigger issue was initializing DRAM controller to be able to
download bigger code (linux kernel + uboot) to external RAM. In
sciphone there is problem that all interesting chips are under metal
shield which is pretty havily soldered. In this case I couldn't read
what kind of RAM memory is mounted without destroying the board (I
don't have such soldering machine which could unsolder so big metal
shield). Thanks to JTAG I could attach to target and then dump DRAM
controller registers from processor running MTK's software, but
setting these values after processor start and configuration of PLL
didn't work.
I decided to disassemble bootloader which could show me how DRAM
controller is initialized and how code fron NAND is loaded (to be able
to flash U-Boot and kernel to NAND so MT6235 will start my code
automatically and I will not have to use JTAG). Currently I have
knowledge how internal MT6235 bootloader is loading code from memory
during startup and I also extracted procedure of DRAM controller
initialization. Thanks to that I'm able to run U-Boot from the very
begining of processor startup.
The problem is that I have just one piece of Sciphone G2 and I don't
want to flash it yet to not break existing code in it. Thanks to
running device I'm able to attach with JTAG and check how peripherals
are configured (i.e. LCD, MMC, etc.). I have backup of flash, but I'm
not 100% sure if I will flash it back, phone will startup. That's why
I bought second piece of Sciphone G2 and should receive it today or on
Tuesday (this Monday is holiday in Poland). In this case I'll flash
U-Boot to NAND and try to make it working. Then we could load the rest
of code from U-Boot (to RAM or NAND over serial).
You can see how my setup looks on attached picture.
The good thing about it is that the same bootloader is used in MT622x,
so it should be fairly easy to do the same on phones based on that
SoCs (but unfortuantely it's just ARM7).
If it comes to code, of course I can share it on "git.osmocom.org".
Currently it's just basic port of U-Boot and not much for linux
kernel, but I'm working on this now so I'll push it when it'll be
ready.
Currently I'm working on driver for NAND memory for U-Boot, so we
could flash linux kernel. When that will be ready I'll push the code.
Then I'll switch to linux kernel and when it'll be functional I also
push the code. At this stage you will not need to have JTAG and you
could load the code over serial in U-Boot.
If it comes to GSM I didn't work with it before. I actualy worked 6
months in L2/3 team for LTE (on RRC) but it's different story.
That could be really outstanding thing if we could run first phone
ever with whole code open (from BB up to APP).
BR,
Marcin
Hi guys,
I dunno if that is the right place for my concern about building the
osmocomBB source. Here is what I already have done:
- downloading the sources for osmocomBB and GNU toolchain for ARM,
- setting the PATH for the arm-elf-* executables,
- calling make in the src directory.
Now, this appears as response of the make command in the terminal:
cd shared/libosmocore/build-host && ../configure
configure: error: cannot find install-sh, install.sh, or shtool in ".."
"../.." "../../.."
make: *** [shared/libosmocore/build-host/Makefile] Error 1.
If you need details about my system, you can look at the following
snippet from the config.log file:
This file contains any messages produced by compilers while
running configure, to aid debugging if configure makes a mistake.
It was created by libosmocore configure UNKNOWN, which was
generated by GNU Autoconf 2.65. Invocation command line was
$ ../configure
## --------- ##
## Platform. ##
## --------- ##
hostname = ubuntu-stefan
uname -m = x86_64
uname -r = 2.6.32-24-generic
uname -s = Linux
uname -v = #41-Ubuntu SMP Thu Aug 19 01:38:40 UTC 2010
/usr/bin/uname -p = unknown
/bin/uname -X = unknown
/bin/arch = unknown
/usr/bin/arch -k = unknown
/usr/convex/getsysinfo = unknown
/usr/bin/hostinfo = unknown
/bin/machine = unknown
/usr/bin/oslevel = unknown
/bin/universe = unknown
PATH: /usr/local/sbin
PATH: /usr/local/bin
PATH: /usr/sbin
PATH: /usr/bin
PATH: /sbin
PATH: /bin
PATH: /usr/games
PATH: /home/stefan/osmocomBB/gnuarm-4.0.2/bin
## ----------- ##
## Core tests. ##
## ----------- ##
configure:2032: error: cannot find install-sh, install.sh, or shtool in
".." "../.." "../../..".
So, I would be very glad, if someone could give me a hint to solve the
problem. Thank you in advance.
Regards,
begy
Hi all, my name is Jose Pereira, and i'm very interested in helping you with
some code! I've wrote the buzzer driver for calypso, not so sure if will
help you of anything, but was just for experimenting :)
Anyway, i send the patch in attachement. The interface can be simply
#include <calypso/buzzer.h>
buzzer_mode_pwt(1);
buzzer_volume(40);
buzzer_note(NOTE(NOTE_E,OCTAVE_5));
Please let me know what do you think of the code, and in what way i can
further help.
Best regards,
--
José Pereira
http://onaips.blogspot.com
Hi All!
At my OpenBSC / OsmocomBB talk here at the Embedded Linux Conference Europe,
one of the attendees (Marcin, see Cc) came to me after the talk and told me he
had recently done a u-boot and Linux kernel port to the MT6235 (that's the
ARM926 based chipsets found in the touchscreen MTK phones).
He said he has no understanding of GSM or the existing MTK firmware, but is
interested in working together with us to try to make the GSM part work.
I think that chipset is very intesting, as we could implement the layer1
inside the Linux kernel (and submit that mainline, yay!) and run our layer2 and
layer3 implementations as userspace processes on the Linux system, together
with the user interface.
The performance of those devices should be somewhere between the Openmoko GTA01
and GTA02, and the GSM stack is certainly not going to eat away a lot of the
CPU either.
I have asked Marcin to write mail to the OsmocomBB mailing list on where we can
find the code. He has so far downloaded the code using JTAG. Combining his
code with our ramloader might remove that JTAG dependency...
Marcin: if you want to push your u-boot / kernel to git.osmocom.org, or want a
separate trac installation for your mtk-linux work, pleaes let me know, I'd be
happy to host that.
Regards,
Harald
--
- Harald Welte <laforge(a)gnumonks.org> http://laforge.gnumonks.org/
============================================================================
"Privacy in residential applications is a desirable marketing option."
(ETSI EN 300 175-7 Ch. A6)
Hi all,
I would like to propose moving the config file into something like ~/.osmocom/
and not put it in a system wide directory. The path in /etc/ is the only
part of OsmocomBB that requires root privileges, and I don't really think
that in a case of multiple users you would want to e.g. share stuff like
the IMSI / Ki anyway.
What do you think?
--
- Harald Welte <laforge(a)gnumonks.org> http://laforge.gnumonks.org/
============================================================================
"Privacy in residential applications is a desirable marketing option."
(ETSI EN 300 175-7 Ch. A6)
Hello,
I'm newbie to osmocomm and GSM too....I'm studying the protocol and the
source code...but I have many doubts...the first one is the following:
1. Which are the routines handling FCCH and SCH in osmocom source code?
2. When I load layer1 firmware and load mobile app, FCCH and SCH are
automatically handled by this application?
Sorry if my questions are stupid for you, but it's a litlle bit complicate
moving in the code, above all for a newbie.
Thanks in advance.
--
View this message in context: http://baseband-devel.722152.n3.nabble.com/FCCH-and-SCH-tp2363201p2363201.h…
Sent from the baseband-devel mailing list archive at Nabble.com.
Hello,
I was walking through trac while I came across this file:
http://bb.osmocom.org/trac/browser/src/host/layer23/src/common/sim.c
I see here:
183 /* send APDU to card reader */
184 static int sim_apdu_send(struct osmocom_ms *ms, uint8_t *data,
uint16_t length)
185 {
186 LOGP(DSIM, LOGL_INFO, "sending APDU (class 0x%02x, ins 0x%02x)\n",
187 data[0], data[1]);
188 l1ctl_tx_sim_req(ms, data, length);
189 return 0;
190 }
ohoh, that's hardcoded.
If we would like to have a software SIM, a SIM in a card reader on the
PC, or a real sim in the MS, I think this would this be the correct
place to plug a modular sim implementation.
I mean something that looks like:
struct osmocom_sim_ops {
int (*sim_apdu_init)(.....);
int (*sim_apdu_fini)(.....);
void (*sim_op_reset)(.....);
void (*sim_apdu_send)(.....);
void (*sim_response_callback)(.....);
};
void ms_register_sim_driver(struct osmocom_ms *ms, struct osmocom_sim_ops *ops);
this could be a part of struct osmocom_ms.
I would be easy to have 3 implementations:
-sim in the mobile, using the current calls 'l1ctl_tx_sim_req'
'l1ctl_tx_sim_conf'
-sim in PCSC using pcsclite or winscard, and a command-line option to
select the reader (by index, by name, or first reader with a card
inside for simple setups)
-virtual sim using pure software
What do you think about this?
Regards
Sebastien
