Cannot enable UART's

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truni

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Dec 30, 2016, 5:45:35 AM12/30/16
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Hi all

I cannot enable UARTS no matter what I try.

See attached for the commands I am sending, has anybody come across this problem before?

My distro information :

Linux beaglebone 4.4.30-ti-r64 #1 SMP Fri Nov 4 21:23:33 UTC 2016 armv7l GNU/Linux

I just cannot get this to work, no does editing uEnv.txt...

Please help :)

Thanks!
FullSizeRender (3).jpg

millsey_386

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Dec 30, 2016, 7:41:03 PM12/30/16
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So I got the bone to boot up by editing the /etc/rc.local file, which is the last script to run upon boot.

However, for some reason although I add both UART-3 and UART-5, the bone only boots with UART-5 enabled. It will boot with only UART-3 enabled if I echo that line out after the UART-5 is echoed.

So I am a step closer but not there yet

Has anybody got a solution as I cannot enable two UART's at the same time.. it's either one or the other...

Is there some pinmux issue going on?

millsey_386

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Dec 30, 2016, 10:18:18 PM12/30/16
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The issue was that I was being stupid

I had a small typo in my rc.local file causing the second line initialising UART2 to be dropped

I now get this output after boot

Last login: Sat Dec 31 03:12:40 2016 from scotts-iphone
debian@beaglebone:~$ su
Password:
root@beaglebone:/home/debian# cat /sys/devices/platform/bone_capemgr/slots
0: PF---- -1
1: PF---- -1
2: PF---- -1
3: PF---- -1
4: P-O-L- 0 Override Board Name,00A0,Override Manuf,BB-UART4
5: P-O-L- 1 Override Board Name,00A0,Override Manuf,BB-UART2
root@beaglebone:/home/debian# ls -l /dev/ttyO*
lrwxrwxrwx 1 root root 5 Dec 31 03:10 /dev/ttyO0 -> ttyS0
lrwxrwxrwx 1 root root 5 Dec 31 03:10 /dev/ttyO2 -> ttyS2
lrwxrwxrwx 1 root root 5 Dec 31 03:10 /dev/ttyO4 -> ttyS4
root@beaglebone:/home/debian#

Next up is using minicom, physically connecting them together and seeing how much of a mess I can make out of that :-)

woody stanford

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Jan 29, 2017, 5:05:54 PM1/29/17
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This DOESN'T WORK but as far as I got.

I thought I would super-duper UART-ize my board. Still waiting for somebody to tell me "how it is done" kinda thing.

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