How to set the serial output of Ubuntu system (i)

1. Platform: Intel X86 Baytrail Platform

2. Since the development mode needs to look at the core serial output, so the Linux system needs to boot from the booting to the part of the system is directed to the serial port, then how to set it?

After installing the Ubuntu system (this is the 14.10 version of Ubuntu system)

(1) First set GRUB parameters:

To modify the/etc/default/grub file:

Modify the following to read:

grub_cmdline_linux_default= "Text Console=tty0 console=ttys0,115200n8"

Then add a line:

grub_serial_command= "SERIAL--unit=0--speed=115200--word=8--parity=no--stop=1"

Then execute the Update-grub to make the configuration effective

(2) Then create the ttys0.conf in the/etc/init/directory with the following contents:

#ttyS0-getty

Start on RC runlevel=[2345]

Stop on RunLevel [!2345]

Respawn

Exec/sbin/getty-l 115200 ttyS0 vt100

Legacy issues:

After the system up, in the Serial port section only displays to:

* Starting regular background program processing daemon[OK]
* Starting Signal sysvinit that alsa-utils tasks is complete[OK]
* Starting CPU interrupts balancing daemon[OK]
* Stopping save kernel messages[OK]
* Stopping Restore sound Card state[OK]
* Starting Cups-browsed-bonjour Remote printer browsing daemon[OK]
* Starting automatic crash report generation[OK]
* Starting Configure virtual network devices[OK]
[OK]toring Resolver State ...
[OK]rting uuid Generator Uuidd
* Speech-dispatcher Disabled; Edit/etc/default/speech-dispatcher
saned Disabled; edit/etc/default/saned
* Stopping System V runlevel compatibility[OK]
* Stopping cold plug devices[OK]
* Stopping log initial device creation[OK]
* Starting save Udev log and update rules[OK]
[150.593006] systemd-logind[947]: Failed to start unit [email protected]: Unknown unit: [Email protected]
[150.602779] systemd-logind[947]: Failed to start User service:unknown unit: [Email protected]

Then there is a display login on the VGA, but the serial port does not display

Further research is needed here

But finally this step is made, the problem behind is the boot script configuration problem

Also explained that, before the purchase of the Baytrail motherboard does not have a serial port hardware problems, small factory do its own motherboard than the brand motherboard to force

How to set the serial output of Ubuntu system (i)