Welcome to the OsmocomBB project

OsmocomBB is an Open Source / Free Software GSM Baseband software implementation.

It intends to completely replace the need for a proprietary GSM baseband software, such as

• drivers for the GSM analog and digital baseband (integrated and external) peripherals
• the GSM phone-side protocol stack, from layer 1 up to layer 3

In short: By using OsmocomBB on a compatible phone, you should eventually be able to make and receive phone calls, send and receive SMS, etc. based on Free Software only.

At the moment we are making very good progress. Most of the hardware drivers have been written, and a minimalistic layer1 and layer2 as well as a mostly untested layer3 exist. Most work is spent on completing functionality and fixing the various known bugs. No work has yet been done on actual voice call support or any sort of UI on the phone.

This is the project page about our experiments (so far) only with phones based on the Ti Calypso/Iota/Rita GSM baseband chipset. The main target is the MotorolaC123. For more supported phones, check below.

We originally intended to build an inexpensive GSM experimentation board built with/around that chipset, but right now are pursuing a slightly alternative course by using cheap off-the-shelf feature phones and write custom software for it.

• The ProjectRationale
• The big MasterPlan
  • AreasOfWork -- What needs to be done and who wants to do it
• Information about the TypicalCalypsoModemDesign
  • Calypso -- The HERCROM digital baseband chip (DSP+ARM7)
    • CalypsoDSP -- The DSP inside the Calypso DBB
  • Iota -- The TWL3025 analog baseband chip (ADC/DAC)
  • Rita -- The TRF6151C GSM transceiver (VCO, up/down-conversion)
• Old/obsolete plan/spec of the GsmDevelBoard (note: This project is on hold right now!
• Description of our own GSM Stack
  • L1A_L23_Interface -- How the Layer1 interfaces with Layer2 and Layer3 of the stack
• Notes on the TSM30 Layer1 as it can be found in the TSM30 source
• Glossary -- The weird terms used in the phone baseband world
• LegalAspects -- Important legal aspects of this project
• People -- The people behind the project
• PressCoverage -- What the press is writing about us

Mailing List

The development discussions regarding this project happen on the baseband-devel@lists.osmocom.org mailing list.

General announcement of major steps and releases of the project are available on the osmocom-announce list.

You can subscribe to any of those mailing lists at http://lists.osmocom.org/mailman/listinfo

IRC (Internet Relay Chat)

We have an IRC channel where some developers and users hang out. You can find it at: irc.freenode.net/#osmocom

Software

Documentation about software developed by this project.

All source code is kept in the git repository at git://git.osmocom.org/osmocom-bb.git

Host programs (running on the PC)

• osmocon -- A tool for Compal phones; to load code into RAM and execute it
• osmoload -- A tool for flashing and examining phones
• calypso_pll -- A tool to calculate Calypso DPLL multiplier+divider
• rita_pll -- A tool to calculate the Rita PLL multiplier/divider
• libosmocore -- A library with utility functions
• layer23 -- An implementation of GSM Layer2 and upwards.
  • WiresharkIntegration -- How to use OsmocomBB with wireshark protocol analyzer

Target programs (running on the phone baseband chip)

• firmware -- The current staging/testing code base for our own software on the Calypso. From it we build a number of apps:
  • hello_world.bin? -- An actual 'hello world' application for LCD and serial port
  • layer1.bin -- The actual Layer1 software as it is to be used with layer23
  • loader.bin -- Our flash loader, dumper and second stage bootloader
  • compal_dsp_dump.bin -- A program to dump the ROM of the DSP inside the Calypso

Supported Phone hardware

Information specific to certain Calypso based phones that we support

• Designed + Manufactured by Compal, OEM by Motorola
  • MotorolaC115/C117 (E87)
  • MotorolaC123/C121/C118 (E88) -- our primary target
  • MotorolaC140/C139 (E86)
  • MotorolaC155 (E99) -- our secondary target
  • MotorolaV171 (E68/E69)
  • SonyEricssonJ100i

• Designed by Openmoko, manufactured by FIC
  • Neo 1973 (GTA01)
  • Neo Freerunner (GTA02)

Accessories

You will need a CalypsoSerialCable to connect the phone to a PC

References

Related projects

• airprobe -- Open Source GSM protocol analyzer
• OpenBSC -- Open Source BSC/MSC/HLR/SMSC
• OpenBTS -- Open Source Um-to-SIP gateway

Recommended reading

• http://laforge.gnumonks.org/papers/gsm_phone-anatomy-latest.pdf -- Introduction to contemporary GSM cellphone hardware
• http://www2.informatik.hu-berlin.de/~goeller/ -- Homepage of Dr.-Ing. Joachim Goeller, lots of GSM tutorials
• http://sourceforge.net/projects/plabs/ -- Source code of the firmware of the Vitelcom TSM30 phone (dead link)
• OsmocomBB presentation at SSTIC 2010

Trac Starting Points

• TracGuide -- Built-in Documentation
• The Trac project -- Trac Open Source Project
• Trac FAQ -- Frequently Asked Questions
• TracSupport -- Trac Support

For a complete list of local wiki pages, see TitleIndex.