Neo FreeRunner Hardware Issues

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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.

Contents

Active Issues

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.

PMU/Charger Issues

Issue: The device may fail to turn on if the battery is deeply discharged, or may fail to charge the battery properly. See for example this thread on the kernel list.

Affects: Unknown. Some discussions on the mailing list may refer to pre-production devices.

Status: Fixed with Werner Almesberger patches - more here

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.

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.

Status: Unknown

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.

Status: Unknown

Workarounds: Edit configuration files (e.g. openocd.conf) to use the IDs that the board is reporting.

Known/Accepted Issues

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.

Resolved Issues

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.
Personal tools

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.

Active Issues

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.

PMU/Charger Issues

Issue: The device may fail to turn on if the battery is deeply discharged, or may fail to charge the battery properly. See for example this thread on the kernel list.

Affects: Unknown. Some discussions on the mailing list may refer to pre-production devices.

Status: Fixed with Werner Almesberger patches - more here

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.

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.

Status: Unknown

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.

Status: Unknown

Workarounds: Edit configuration files (e.g. openocd.conf) to use the IDs that the board is reporting.

Known/Accepted Issues

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.

Resolved Issues

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.