baseband-devel January 2013

baseband-devel@lists.osmocom.org

40 participants
71 discussions

is the Viterbi decode for the AFS provided by Sylvain right?

by bob

Hi ,List: search some materials, find that the decode method of AFS convolutional code is different from the EFS`, it use RSC, and need SOVA(soft output viterbi algorithm). am i right? -- View this message in context: http://baseband-devel.722152.n3.nabble.com/is-the-Viterbi-decode-for-the-AF… Sent from the baseband-devel mailing list archive at Nabble.com.

12 years, 4 months

Structure of traffic data in burst_ind messages

by Bhaskar11

I'm experimenting with burst-ind branch and am able to track control messages in ccch_scan. I then send an Assignment Command to change to a traffic channel. I can see the bursts come in, but cannot make out the format of the data. If I understand right, the burst_ind structure holds 15 bytes of data, but the traffic data should be 33 bytes. I assume the traffic data is spread across several burst-ind messages. Can you please clarify how to re-assemble the full 33-byte traffic data structure from the burst_ind messages? Thanks. B.

12 years, 4 months

Hardware replacement for uplink sniffing

by Roddy Ernest

Hello, I know that there is a hardware replacement kit that is available for Osmocombb phones that help make the phones be used as uplink sniffers, but unfortunately the kit uses components that operate in the European GSM bands. Are there any hardware replacement kits for Osmocombb phones that operate in the U.S. GSM frequency bands? Sincerely, Roderick Ernest

12 years, 5 months

Decoding AMR

by Bhaskar11

I've been experimenting with decoding AMR in burst_ind with the following steps: 1. Ignore SACCH and UL frames 2. check for FACCH 3. check for CMI/CMR (only on specific frame numbers) and change codec if necessary after 12 frames 4. check for RATSCCH, if necessary change codec after 12 frames Can anyone confirm that this is the proper process? I've looked at Bob's code of July 2012. It does not use the above checks which may be the reason for its failure. B. ===================== From: bob <avwiseav <at> gmail.com> Subject: is my patch for capturing TCH frame correctly?<http://news.gmane.org/find-root.php?message_id=%3c1342688308441%2d4025199.p…> Newsgroups: gmane.comp.mobile.osmocom.baseband.devel<http://news.gmane.org/gmane.comp.mobile.osmocom.baseband.devel> Date: 2012-07-19 08:58:28 GMT (27 weeks, 6 days, 20 hours and 14 minutes ago) Hi, everyone interesting the topic, this is my latest patch for TCH decode, fix few bug; but it not work well for TCH AMR decode, welcome everyone interesting it to review it and modify it! the most problem now I think is the capture of the Correct TCH frame, at the last ,there is some output for analysis --- app_ccch_scan.c 2012-03-14 16:08:11.305112000 +0800 +++ new_app_ccch_scan.c 2012-07-19 15:32:31.945314000 +0800 <at> <at> -50,20 +50,80 <at> <at> #include <l1ctl_proto.h> #include <osmocom/bb/misc/xcch.h> +#include <codec.h> +#include "conv_tch_afs.h" +//#include "../openbtsstuff/GSML1FEC.h" +//extern bool TCHFACCHL1Decoder::processBurst( const RxBurst& inBurst); +//const struct osmo_conv_code conv_tch_afs_12_2; +extern FILE *log_tmsi; extern struct gsmtap_inst *gsmtap_inst; +FILE *d_speech_file; +const unsigned char amr_nb_magic[6] = { 0x23, 0x21, 0x41, 0x4d, 0x52, 0x0a }; +

12 years, 5 months

Help with JTAG

by teslarode＠yahoo.com

Hello, I've found a very interesting article about SciphoneDream G2 published on your webpage at http://bb.osmocom.org/trac/wiki/SciphoneDreamG2 that covers pretty detailed information about MT6235 SoC, bootstrapping as well as JTAG. This is the only article I have ever found on internet about MTK SoC and JTAG. What I am trying to accomplish is to access NAND flash and write to it over JTAG (in order to recover from corruption after bad flash) on MTK8555 SoC which according to my in-depth research and analysis has very similar architecture to MT6235. If I can't write to NAND over JTAG but would be able to launch u-boot that would be a solution too. I am very good at ARM assembly and debugging, however I am not very experienced with JTAG. Do you think you (or anyone else) could help me out, by giving me guidance what hardware, software, config files should I use to make JTAG work on this SoC ? Any help or advise would be more then appreciated! If you are a wrong person I contacted, I apologize for the inconvenience. Many thanks in advance! Dwayne

12 years, 5 months

Mistake in gsm_04_08.h channel mode definition

by Bhaskar11

In enum gsm48_chan_mode definitions we have: GSM48_CMODE_DATA_3k6 = 0x23, It should be 0x13 as in 3GPP TS 04.08 / 10.5.2.6. Please update in repository.

12 years, 5 months

thanks for osmocom, my goals, available to test c139 & c115

by Craig Comstock

Hi, I have bought two phones... Motorola C139 and Motorola C115. I'm using the raspberry PI UART instead of a dedicated cable and got the hello world example working just fine on the C115. My goal is to have a usable open source phone which I see there is a bit of a start at in the source code. I've been working on getting debian on my Motorola Defy for a while and am making some progress. Since I have two phones... I am certainly willing to help in testing things. I can't promise a lot of time but I can hope to help a little. Thanks for your efforts, Craig Comstock Lawrence, KS

12 years, 5 months

another method for filter rework

by Akib Sayyed

Dear sylvain I checked on your website you gave some other way of doing filter rework. I checked tried to check problem n checked possible shorts. but multi meter shows all part are shorted. also checked each components but it shows that there is direct connection in between all points of baluns. i would like to try other way for same -- Akib Sayyed Matrix-Shell akibsayyed(a)gmail.com akibsayyed(a)matrixshell.com Mob:- +91-966-514-2243

12 years, 5 months

Dumping DSP

by Akib Sayyed

Dear list i see there is target_dsp firmware. as per readme found inside it dumps dsp data on console. but i am unable to compile. it needs tic54x-coff but couldnt find it. can any one guide me through this. -- Akib Sayyed Matrix-Shell akibsayyed(a)gmail.com akibsayyed(a)matrixshell.com Mob:- +91-966-514-2243

12 years, 5 months

Implementing AMR Codec for Mobile App

by Akib Sayyed

Dear All Currently i am trying to implement AMR codec for Mobile App. Please guide me for same. I am not that good in channel decoding. if anyone have given a try or have partial code implementation please help me in that. -- Akib Sayyed Matrix-Shell akibsayyed(a)gmail.com akibsayyed(a)matrixshell.com Mob:- +91-966-514-2243

12 years, 5 months

2025

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

baseband-devel January 2013