Neo FreeRunner Hardware Issues
This is a community-written page that discusses hardware issues with the Freerunner/GTA02 device. Information here is unofficial (and possibly incorrect) unless otherwise stated. Corrections and clarifications from Openmoko employees would be greatly appreciated.
Also please DON'T PANIC when reading this page. Please give Openmoko employees time to investigate these issues and to develop a solution. Some of the items may turn out to be non-issues, or may have software workarounds.
GPS Slow TTFF
Issue: The GPS signal is degraded to the point where the unit cannot reliably get a "cold-start" fix. See GPS_Problems.
Reason #1: For some reason, the MicroSD controller on the Freerunner is interfering with GPS reception.
Reason #2: Poor soldering and/or mechanical deformation of the internal GPS antenna connector on some devices. See FreeRunner_GPS_antenna_repair_SOP
Affects: unknown percentage of devices
Status: Software workaround found; hardware fix under investigation.
Workarounds: Remove the microSD card. Use an external GPS antenna. Supplying almanac data and approximate coordinates in software (so that the chip can perform a "warm" acquisition) may also help.
Poor Audio Quality
Issue: The person on the other end of a GSM phone call may experience poor audio quality, to the point where he/she cannot carry on a normal conversation.
There are three related aspects to this issue:
- Call is too quiet (mixer settings for mic and/or earpiece are set too low)
- Caller hears a loud echo of their own voice #1267
- Buzzing noise caused by GSM radio interference #883 #1352
Affects: all devices but only some users (depending on many factors)
Status: Under investigation. There is a possibility that the quality can be made "good enough" through software (mixer settings).
Workarounds: Using a bluetooth headset is a possibility.
Issue: The device may fail to boot or charge the battery if the battery is deeply discharged (far enough that its internal protection circuitry is activated). See for example this thread on the kernel list.
If the battery's terminal voltage is low but greater than zero then the Neo1973 recovery method may work: Disconnect USB, remove the battery, wait 10 seconds, re-insert the battery, re-connect USB, let it charge for 1 hour (or more) without pressing any buttons.
Affects: Unknown. Some discussions on the mailing list may refer to pre-production devices.
Workarounds: See http://lists.openmoko.org/pipermail/community/2008-July/021556.html
Some SIMs Don't Work
Issue: There are reports that some users cannot register with their GSM network when using certain SIM cards. See for example http://lists.openmoko.org/pipermail/community/2008-July/020370.html
Recent investigations suggest that this is related to the voltage specification of the SIM - "2.9V" works while "1.8V" may have problems.
Note that there have also been a couple of reports where the failure to register was caused by an incorrectly-mounted SD card (which in turn prevented the SIM from making proper electrical contact).
Note also that there was a related issue with certain AT&T SIMs in early Neo1973 devices. The Freerunner is shipping with a newer GSM firmware in which the original Neo1973 issue has been fixed. http://wiki.openmoko.org/wiki/Carriers/ATT
Affects: Only a subset of users (details unknown).
Status: Under investigation
Workarounds: It may be possible to obtain a different model of SIM from your GSM carrier.
Empty NOR Flash
Issue: NOR flash (backup copy of u-boot) is not programmed. #1568
Affects: Unknown - maybe only 1 or 2 devices? Also need to confirm that the bug report was from a mass-production unit rather than an earlier prototype.
Workarounds: Use the NAND copy of u-boot and be careful not to brick the device unless a debug-board is available.
Debug board has wrong vendor/product ID
Issue: A debug board is not reporting the expected USB Vendor/Product ID.
Affects: Only one report has been seen so far.
Workarounds: Edit configuration files (e.g. openocd.conf) to use the IDs that the board is reporting.
This section lists items that are acknowledged as being less than ideal, but are considered to be acceptable in the shipping product. They will not be discussed in detail on this page.
- Poor performance + slow bus speed of the Glamo GPU - discussed to death on the mailing lists and IRC.
- GPS antenna switch driven out-of-spec - does not appear to have a significant effect on device performance
- Poor low-frequency audio response with low-impedance headphones, e.g. as discussed in this thread: http://lists.openmoko.org/pipermail/openmoko-kernel/2008-March/001999.html (NOTE - this thread refers to pre-mass-production devices)
These are issues that have been discussed in the past, but have been fixed (or turned out not to be a problem) for the mass-produced devices.
- Excessive LED current - Some early units lacked a current-limiting resistor for the LEDs. This has been fixed for the production units.
- Battery life - At this time it appears that the Freerunner battery life will be acceptable once suspend/resume support has been implemented in software.