Hi,

I'm using a BBB with Debian on an SD card, and am having issues booting up 
whilst Pin 31 on P8 is held low.

When P8.31 is held high, i.e. held at 3V3, or not connected to anything, 
the normal boot-up sequence occurs. I can see LEDs D2 to D5 flashing, and 
can see the standard boot-up output from the debug serial connection on my 
terminal emulator. 

When P8.31 is held low, i.e. 0V, all 4 LEDs light up, but remain lit and 
don't flash. It appears the BB doesn't finish it's boot-up sequence, and am 
unable to communicate with it via ethernet/USB. Viewing the Debug output 
doesn't help either as no matter what speed I select on my PC's terminal 
emulator, it outputs garbage characters. After a few seconds all 4 LEDs 
turn off and appears as though it tries to boot again as all 4 LEDs light 
up.

Holding the boot switch (S2) on the BBB and then applying power has no 
affect on the observations described above.

P8.31 is to be used as UART5 CTS and is connected to R2OUT of a 
MAX13234EEUP+ RS232 converter on a custom board. When P8.31 is connected to 
the RS232 Converter, this pin is held low.

In the /boot/uEnv.txt file I have the following lines enabled to allow 
P8.31 to be used as UART5's CTS:
uboot_overlay_addr3=/lib/firmware/BB-UART5-00A0.dtbo
uboot_overlay_addr4=/lib/firmware/BB-UART5-RTSCTS-00A0.dtbo

disable_uboot_overlay_video=1
disable_uboot_overlay_audio=1

However enabling/disabling these lines seem to make no difference to the 
boot-up issue.

Any help with this would be appreciated.
Thanks in advance,
Adam.

-- 
For more options, visit http://beagleboard.org/discuss
--- 
You received this message because you are subscribed to the Google Groups 
"BeagleBoard" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to beagleboard+unsubscr...@googlegroups.com.
To view this discussion on the web visit 
https://groups.google.com/d/msgid/beagleboard/c4141afb-26f3-40da-aeae-9481a215e5d6n%40googlegroups.com.

Reply via email to