gta02-core is a community project to create a new hardware revision of the gta02 hardware, christened and introduced by werner in a mail to the gta03 list
Development discussions are happening on the  mailing list,and archives can be found here . All the project files (schematics and component models etc.) are stored in openmoko's public SVN server at 
What is gta02-core?
gta02-core is an experimental project to explore community involvement in the development of hardware for potential future open phones. The aim is to develop an incremental improvement on existing GTA02 designs, while replicating the necessary CAD files in a open format.
The primary improvement over the GTA02 design will be removal of the Glamo graphics device, relying on the S3C2442's direct LCD interface. This removes the minimal graphics acceleration offered by the Glamo with the benefit of vastly improved bandwidth. This is expected to allow better software graphics acceleration, and easier streaming of video data from SD cards. While some individual (currently accelerated) operations may be slower without Glamo, it's expected that Glamo removal will overall offer a performance increase.
In detail, the hardware changes planned for gta02-core are:
- Remove Glamo
- Remove the audio amp
- Remove NOR
- Remove one accelerometer and connect both interrupts of the remaining one
- Move LCM to CPU interface (as used in GTA01)
- Move Wifi to SPI (see Werner's rework)
- Remove U4401 etc. (external GSM serial access through headphone jack)
The gta02-core project is primarily a test-bed for the community development process. While it's hoped to take the process through working prototypes, the project is not intended to result in a mass-production phone.
If the community succeeds in the gta02-core project, development of a GTA03 may follow similar lines with community involvement in specifying, designing and developing the hardware.
What is gta02-core NOT?
gta02-core is not gta03. It's not a 'next gen' phone from openmoko. It's not a significant departure from existing gta02 devices. It won't even be a usable phone...
Many hardware changes have been proposed for gta03, gta02.5 or gta02-core. The following hardware changes have been proposed, but are NOT part of the gta02-core plan:
- adding a camera
- changing GSM chips (i.e. no 2.5G or 3G)
- de-NANDification (but NAND use for anything but storing Qi and "factory" data is discouraged)
- changing WIFI chip
- replacing the SoC with a 6410
- integration of IDBG
- changes to the ID (case)
- a multi-touch screen
- SIR / CIR
- additional I/O connectors
Basically - the "new ground" we are breaking is in the project and the organisation, not in the device we are producing. The hardware that comes out the end is intended to NOT be a significant step away from work already done, allowing us to foucs on the process, over new technical challenges.
What is not yet decided gta02-core or NOT?
Changes to the casing, see CAD models.
Plan and Progress
(simplified from the workflow diagram)
- Create and review component diagrams
- Create and review Schematics
- Create and review device footprints
- Create and review layouts
- Produce PCBs
- SMT / populate PCBs
The PCB production and populating will need to be conducted by third party businesses, and the gta02-core project will need to find funding to support these activities.
How can I help?
Join the gta03 mailing list. Grab a copy of KiCad and get on with reviewing or submitting changes. Most of the current effort involves comparing our schematics to datasheets and to the gta02 schematics released by openmoko.
- Install KiCad
- Checkout the gta02-core repository (svn co http://svn.openmoko.org/trunk/gta02-core/)
- fire up the gta02-core project and start contributing!
- Submit patches to the mailing list as you would for software projects (svn diff > XXX.patch)