Question on hardware problem with my original GTA01 phone
go at l5.org
Tue Jul 22 20:16:30 CEST 2008
Shortly after I received my original GTA01, it developed a problem where
it won't run (i.e. powers off abruptly) when plugged into a USB port and
enumerated (i.e if I plug it into a USB port with no 'driver' on the
host side, nothing happens.) I suspect it has something to do with the
charging circuit shutting off power somehow, since a charged battery (I
have a spare that is still charged and can charge reliably on my new FR)
runs the unit fine until I plug into the USB.
The problem is that this failure prevents me from doing any kind of
flashing of the software - assuming it might be a software bug - since
presence of USB stops the unit cold. I *have* a debug board, but have
been, so far, unable to do anything with it that resembles 'debugging'.
It's likely caused by the older Debian I'm running on my main
development machine, but nevertheless, using the debug board seems
problematic at this point. (I do a lot of embedded stuff in my 'day'
job, much of it under Linux, so I'm not a novice at ICE or debug pods,
but, as I said, the difficulties are likely due to 'libraryitis' on my
old system - I haven't tried the tools on a more recent Ubuntu 8.04,
which is what I'm using for most work these days.)
So, the questions are:
1) Is this likely a hardware failure and if so, can someone point me to
the component that needs replacing? I do have appropriate surface mount
rework tools, hot air and such, so can perform basic rework (no BGAs
2) Is there any way to bypass this feature (e.g. running the USB
connection to the Neo by inhibiting the power connection?)
By the way, this problem originally showed up after the unit had sat for
a lengthy time on the USB port 'charging'. I never had the 'loud buzz'
problem some have mentioned. It just stopped working. Unfortunately,
while using the debug board for power injection, I attempted to flash
the software sometime after the problem arose and the unit decided to
summarily power off during the rootfs flash, and has been the same ever
since. The debug board power injection doesn't seem to help anymore. I
was running the original uboot (came with the unit or was initially
flashed just after receiving it - I don't remember) at the time of the
failure. I WAS able to flash a new uboot (at least new at the time) and
that had no effect.
So if anyone can peek at the schematics for GTA01 and let me know if
this sounds like a simple fix, I'd like to get my old Neo up and running
again, for nostalgia, if nothing else.
More information about the hardware