Tuesday, July 26, 2011

Baudrate issue in Beagleboard Xm

While working with Beagleboard Xm I faced a strange issue related to baud rate.
My setup:
   1. Beagle Board Xm
   2. Acer 4930 Laptop
   3. 5v,3Amps supply for Beagleboard
   4. USB to serial converter. [Detected as /dev/ttyUSB0 - minicom is used on host side]
The issue:
  1. Getting jumbled characters in u-boot menu at times
  2. This continues even if the kernel is up.
Solution:
For u-boot:
Change the current baudrate "setenv baudrate 19200"
Change the baudrate in minicom "CTRL A,Z; O; Serial Port Setup; E; B(Require times for 19200)"
For seeing the kernel messages:
Before booting the kernel set the proper bootargs to be passed.
"setenv bootargs console=ttyS2,19200n8"
NOTE: The kernel boot-up messages could be seen; but the login prompt is not seen due to the issue. Here change back minicom(host side) baud rate to 115200.
Now the login prompt could be seen; but the jumbled character issue would be there.
Still login using the required credentials.
After logging in:
Use the shell command to change baudrate of required serial port
"stty -F /dev/ttyS2 speed 19200"

Sunday, July 24, 2011

BeagleboardXm Experiments

Install "u-boot-tools" also to use mkimage.
#sudo apt-get install u-boot-tools


Start Here with Beagle Board Xm

==================================
Build Root: Download source errors
1. genext2fs -> http://sourceforge.net/projects/genext2fs/files/
2. fakeroot --> http://sources.buildroot.net/
STEPS:
1. make menuconfig
2. Select - Build Options
3. Select - Mirrors and Download locations
4. Set "Primary Download site" as "http://sources.buildroot.net/"
===================================

Thursday, July 14, 2011

How to configure vi for source code browsing?

Install
1. Install ctags
The ctags program which is written by the VIM team is called " Exuberant Ctags" and supports the most features in VIM.Use it.
2. Install cscope
3. Download and place "cscope_maps.vim" plugin in your directory "$HOME/.vim/plugin".
[If the directories are not there, create them using mkdir command]


Create Database for ctags & cscope
In your source code directory:
    1. ctags -RV
    2. cscope -Rvb


How to navigate?
Place cursor on any symbol(function name,variable...) & press the key combinations.
1. ctags:
    CTRL + ], SHIFT + 8, CTRL + T, CTRL + I, CTRL + O
2. cscope
    CTRL + \ + s

Advanced Vi Tutorial