Board with apparently broken serial port (tx) looking for advice...

[Josh Karabin]

I received a beagle board this week. It started out ok, but over a few
hours the serial port output from the board starting acting weird, and
then it just stopped outputting characters altogether. I'm not sure what
caused it. Any ideas?

When I received it, I successfully downloaded a kernel and one of the
pre-canned ramdisk filesystems from the wiki to it via u-boot y-modem.
The kernel booted just fine and seemed ok. If memory serves, I used the
"poweroff" or "reboot" or "reset" command (not sure which) to shut down
the system. I may have had to remove power, I can't say for sure.

After resetting the board, I noticed that serial output had started to
degrade - minicom seemed to be receiving the same FIFO's worth of data
over and over. After a number of reboots during which I was messing with
my PC's serial hardware to see if the problem was on the PC's end, the
beagle board stopped outputting serial characters altogether.

I've noticed that I can type "reset" after waiting a reasonable amount
of time for u-boot to get to its command prompt (which I can't see).
When I do that, the USR0 and USR1 LEDs shut off, and then come back on.
It appears that the beagle is receiving characters just fine from its
UART, but it's failing to output them. I've since verified that my
minicom + serial port combo is working with a loopback test.

I've also heard audio output from the headset port, a short buzzing
sound. I presume that's normal for u-boot's audio test?

I've since written an MMC card with a MLO, uImage, and u-boot.bin, and
tried booting off that. I see the same lack of output on the serial
port, and continue to hear the same audio tone from u-boot. I can't
really tell if I actually booted from MMC, since I don't get any serial
output.

Does this sound familiar to anyone? I've tried power both from a powered
USB hub and a DC supply with the same results. I'm hoping there's
something obvious to look for before sending the board back.

Thanks,

- Josh

[Gerald Coley]

This is familiar. This is an issue we have seen with some faulty serial devices on the board that seem to go bad, usually in one direction. We have increased our burn in time to sort these issues out, but some of the early shipments got a lower burn in time before we increased it.

 

You need to send it in for repair as soon as possible. Go to the support page and submit an RMA request. http://beagleboard.org/support/rma 

 

Return the board to:

Beagle Hospital

675 North Glenville #195

Richardson, TX 75081

 

Gerald

[Josh Karabin]

Glad to hear it's a known issue. Thanks, Gerald. I'll get it out the
door tomorrow.

- Josh

[cian+bea...@cia.nhugh.es]

Hi all,

My board arrived today. Serial TX works OK most of the time. Serial RX
was flakey at first and is now totally dead. I can see 3.3v level
serial on pin 9 of U10. I can see 1.8v level serial on TP21 but NOT
TP22.
On TP22 I see 1 to 1.1v with no serial. I suspect that U9 (the
txs0102) is at fault here.

Any thoughts on this? Might it be the same issue?

Furthermore, occasionally the U-Boot output appears to loop back on
the RX line, producing something like the following:
(U-Boot appears to be trying to parse it's own output)

U-Boot 1.3.3-00035-gab55ae5-dirty (Jun 16 2008 - 17:35:22)

OMAP3530-GP rev 2, CPU-OPP2 L3-165MHz
OMAP3 Beagle Board + LPDDR/NAND
DRAM: 128 MB
NAND: 256 MiB
In: serial
Out: serial
Err: serial
Audio Tone on Speakers ... complete
OMAP3 beagleboard.org #
OMAP3 beagleboard.org #
OMAP3 beagleboard.org #
OMAP3 beagleboard.org #
OMAP3 beagleboard.org # U-Boot 1.3.3-00035-gab55ae5-dirty (Jun 16 2008
- 17:35:22)
Unknown command 'U-Boot' - try 'help'
OMAP3 beagleboard.org #
OMAP3 beagleboard.org #

Texas Instruments X-Loader 1.41
Starting OS Bootloader...


U-Boot 1.3.3-00035-gab55ae5-dirty (Jun 16 2008 - 17:35:22)

OMAP3530-GP rev 2, CPU-OPP2 L3-165MHz
OMAP3 Beagle Board + LPDDR/NAND
DRAM: 128 MB
NAND: 256 MiB
In: serial
Out: serial
Err: serial
Audio Tone on Speakers ... complete
OMAP3 beagleboardf L???B
Unknown command 'f' - try 'help'
OMAP3 beagleboard.org #2(
Unknown command '2(' - try 'help'
OMAP3 beagleboard.org #
OMAP3 beagleboard.org #
??*A



Many Thanks,

C

On Aug 4, 3:40 am, "Gerald Coley" <ger...@beagleboard.org> wrote:
> This is familiar. This is an issue we have seen with some faulty serial
> devices on the board that seem to go bad, usually in one direction. We have
> increased our burn in time to sort these issues out, but some of the early
> shipments got a lower burn in time before we increased it.
>
> You need to send it in for repair as soon as possible. Go to the support

> page and submit an RMA request.http://beagleboard.org/support/rma

>
> Return the board to:
>
> Beagle Hospital
>
> 675 North Glenville #195
>
> Richardson, TX 75081
>
> Gerald
>

[Cian Hughes]

[Cian Hughes]

[Cian Hughes]

My board arrived today. Serial TX works OK most of the time. Serial RX
was flakey at first and is now totally dead. I can see 3.3v level
serial on pin 9 of U10. I can see 1.8v level serial on TP21 but NOT
TP22.
On TP22 I see 1 to 1.1v with no serial. I suspect that U9 (the
txs0102) is at fault here.

Occasionally I see the TX output looping back onto the RX line at
power on time, producing the following as uBoot tries to parse its own
output:

Any thoughts on this? Might it be the same issue?

Many Thanks,

C

On Aug 4, 3:10 am, Josh Karabin <gkara...@vocollect.com> wrote:
> I received a beagleboardthis week. It started out ok, but over a few
> hours theserialportoutput from theboardstarting acting weird, and

> then it just stopped outputting characters altogether. I'm not sure what
> caused it. Any ideas?
>
> When I received it, I successfully downloaded a kernel and one of the
> pre-canned ramdisk filesystems from the wiki to it via u-boot y-modem.
> The kernel booted just fine and seemed ok. If memory serves, I used the
> "poweroff" or "reboot" or "reset" command (not sure which) to shut down
> the system. I may have had to remove power, I can't say for sure.
>

> After resetting theboard, I noticed thatserialoutput had started to

> degrade - minicom seemed to be receiving the same FIFO's worth of data
> over and over. After a number of reboots during which I was messing with

> my PC'sserialhardware to see if the problem was on the PC's end, the
> beagleboardstopped outputtingserialcharacters altogether.

>
> I've noticed that I can type "reset" after waiting a reasonable amount
> of time for u-boot to get to its command prompt (which I can't see).
> When I do that, the USR0 and USR1 LEDs shut off, and then come back on.
> It appears that the beagle is receiving characters just fine from its
> UART, but it's failing to output them. I've since verified that my

> minicom +serialportcombo is working with a loopback test.
>
> I've also heard audio output from the headsetport, a short buzzing

> sound. I presume that's normal for u-boot's audio test?
>
> I've since written an MMC card with a MLO, uImage, and u-boot.bin, and

> tried booting off that. I see the same lack of output on theserialport, and continue to hear the same audio tone from u-boot. I can't

[Ragha]

Gerard,

On Sun, Aug 3, 2008 at 9:40 PM, Gerald Coley <ger...@beagleboard.org> wrote:
> You need to send it in for repair as soon as possible. Go to the support
> page and submit an RMA request. http://beagleboard.org/support/rma
>
> Return the board to:
>
> Beagle Hospital
>
> 675 North Glenville #195
>
> Richardson, TX 75081

my board has hit this issue yesterday.
Is it possible to drop the board to this address?

-Ragha

[Gerald Coley]

You need to fill out the RMA form on the beagleboard.org site.

 

Gerald