MT7601 on Raspberry Pi

Here's how to cross compile driver for Mediatek MT7601 based wifi dongle.

Before this, you need to compile your own raspibian kernel, see my old post: http://igunosystem.blogspot.co.id/2014/03/step-by-step-building-raspibian-on.html
After above process is OK, You'll have compiled kernel source and working root file system with working chroot (using qemu-arm-static) for raspberry pi board on your Desktop PC.

mt7601
download source:
https://github.com/porjo/mt7601/archive/master.zip
or
git clone https://github.com/porjo/mt7601.git

RTL8188eu on Raspberry pi

Here's how to cross compile driver for RTL8188eu based wifi dongle

Before this, you need to compile your own raspibian kernel, see my old post:
http://igunosystem.blogspot.co.id/2014/03/step-by-step-building-raspibian-on.html
After above process is OK, You'll have compiled kernel source and working root file system with working chroot (using qemu-arm-static) for raspberry pi board on your Desktop PC.

download source:
https://github.com/lwfinger/rtl8188eu/archive/master.zip
or
git clone https://github.com/lwfinger/rtl8188eu

WVDIAL Keep Alive

Here's a script to make the wvdial keep alive. Similar to umtskeeper that use sakis3g, this one can be use for some modem or internet provider that sakis3g won't connect. let's call this script as runwvd.
runwvd: (moved to github)

https://github.com/huntu2/wvdial-keepalive/blob/master/runwvd

make the script executable
chmod a+x runwvd

change the MODEM_NAME to your modem vendor that shown by lsusb

To start do following:
sudo ./runwvd start

To stop:
sudo ./runwvd stop

To view progres:
tail -f /tmp/runwvd.log

Prerequisites:
Before above script able to run properly, you'll need package:
sudo apt-get install wvdial usb-modeswitch fping ppp nohup usbutils

configure wvdial.conf by executing
sudo wvdialconf

copy the result at /etc/wvdial.conf and place it in the same folder as this script. Complete the Phone number username and password, something like this
wvdial.conf:
#-----------------------------------------------
[Dialer Defaults]
Init1 = ATZ
Init2 = ATQ0 V1 E1 S0=0 &C1 &D2
Modem Type = Analog Modem
ISDN = 0
Modem = /dev/ttyUSB0
Baud = 9600
Phone = *99#
Username = '0'
Password = '0'
#------------------------------------------------

the '0' means no username and password supplied.

You also need resetusb, here's the source:
resetusb.c
#----------------------------------------------------
#include <stdio.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/ioctl.h>
#include <linux/usbdevice_fs.h>
void main(int argc, char **argv)
{
    const char *filename;
    int fd;
    filename = argv[1];
    fd = open(filename, O_WRONLY);
    ioctl(fd, USBDEVFS_RESET, 0);
    close(fd);
    return;
}
#----------------------------------------------------
compile it using:
gcc -o resetusb resetusb.c

Brief how it works:

The runwvd start with stamp file (/tmp/.runwvd) to control the loop, if this file gone, the loop will stop and the script terminated. The output process can be shown at /tmp/runwvd.log and the wvdial progress can be monitored from /tmp/wvdial.log.
 
First, it will call wvdial with wvdial.conf at the same folder. Then every SLEEPTIME period (above is 3 second) will regularly check for ppp0 existence and wvdial process. If both is missing, then the script will kill the wvdial and redial again.
 
Second, if first step is passed , the script will try to ping the dns server on peride CHECKTIME x SLEEPTIME, (above every 3x60=3minutes). The IP of the DNS were taken from /etc/resolv.conf resulted by wvdial upon successful connection. The ping loop will try to reach the DNS server for PINGLIMIT times (above is 5) with 1 second delay each. If all fail, then the script will terminate the wvdial and redial again.
 
Third, if the redial process happen more than REDIALIMIT (above is 5 times), then the script will try to reset the 3G modem after the wvdial terminated, and then redial again. This will help to re-register the 3G modem to the mobile network base station.
 
This note was written for my own record continuing previous blog on my homemade 3g router, but this might be useful for others who need it. 
Sorry for the bad blog format due to  my poor knowledge of the HTML and english language.

Routing subnet below net

iptables -t nat -A POSTROUTING -o ppp0 -j MASQUERADE

iptables -I FORWARD -i br0 -o 10.1.1.60 -s 10.1.1.0/24 -d 10.1.2.0/24 -j ACCEPT
ip route add 10.1.2.0/24 via 10.1.1.60

iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE
iptables -A FORWARD -i eth0 -o wlan0 -s 10.1.1.0/24 -d 10.1.2.0/24 -j ACCEPT

Sudo no password

all user no password

sudo visudo
..

ALL ALL=(ALL) NOPASSWD:ALL

 

spesific user no password

 

sudo visudo

....

<user> ALL=(ALL) NOPASSWD:ALL

Duplicating Raspberry Image The hard Way

Compressed backup system

Insert sdcard containing working raspberry system
says it way detected as /dev/sdc/

copying the partition
sudo sfdisk -d /dev/sdc > partition.layout

mounting the sdcard
sudo mount /dev/sdc2 /mnt
sudo mount /dev/sdc1 /mnt/boot

compressing your system
cd /mnt
sudo tar cjvf /home/user/imagerpi-0000.tar.bz2 *

unmounting sdcard
cd ~
sudo umount /mnt/boot
sudo umount /mnt
unplug your sdcard

Cleanup log file

Simple script to clean up log file
vi cleanlog

#-------------------------------------------------------
#!/bin/bash

# Make sure only root can run our script
if [ "$(id -u)" != "0" ]; then
   echo "$0 must be run as root" 1>&2
   exit 1
fi

if [ "$1" ];then
   LOGDIR=$1
   if [ ! -d "$1" ];then
      echo "$1 not exist"
      exit 0
   fi
else
   LOGDIR="/var/log"
fi

Pretty OSMC

Just download the latest osmc for Raspberry, burn it to sdcard and plug.
Install kore at your android, enable service->webserver->remote http at your osmc,
Huray... i got media centre with remote control :)

The same does with openelec and xbian, it's pretty, and off course available for raspberry pi.

Clock skew detected. Your build may be incomplete.

Happen to me many times, and keep forgeting this:

find . -exec touch {} \;

Bye bye "Clock skew detected. Your build now can be completed." :)

Running Xorg From rc.local as common user

To start Xserver with no desktop manager at boot time and run as common user, simply put this line at /etc/rc.local
setsid sh -c 'su -c startx username <> /dev/tty1 >&0 2>&1' &

Replace the startx with your Xserver application such as startxfce, startlxde etc.

In my system i want to run the xterm on 1024x768 monitor with whole area active, no need mouse moved to active xterm area, says the geometri of xterm to cover whole area would be 170x59 character size, the command became:
setsid sh -c 'su -c "xinit -geometry 170x59" username <> /dev/tty1 >&0 2>&1' &

Ref: http://unix.stackexchange.com/questions/146758/how-do-i-run-as-a-limited-user-while-logged-in-as-root-and-another-question

VIm Cheatsheet

Cursor movement
h - move cursor left
j - move cursor down
k - move cursor up
l - move cursor right
w - jump forwards to the start of a word
W - jump forwards to the start of a word (words can contain punctuation)
e - jump forwards to the end of a word
E - jump forwards to the end of a word (words can contain punctuation)
b - jump backwards to the start of a word
B - jump backwards to the start of a word (words can contain punctuation)
0 - jump to the start of the line
^ - jump to the first non-blank character of the line
$ - jump to the end of the line
G - go to the last line of the document
5G - go to line 5
Tip Prefix a cursor movement command with a number to repeat it. For example, 4j moves down 4 lines.

Frame Buffer Set on Banana Pi

When you plug the HDMI of Banana Pi running Bananian to low resolution TV or Monitor, you won't get proper display.  To correct this use the frame buffer setting,

sudo apt-get install fbset

Replace the /etc/fb.modes, fill it with these lines:
mode "640x480-60"
    # D: 25.200 MHz, H: 31.500 kHz, V: 60.001 Hz
        geometry 640 480 640 960 32
        timings 39682 48 16 33 10 96 2
        rgba 8/16,8/8,8/0,8/24
endmode

mode "768x576-75"
    # D: 49.188 MHz, H: 46.580 kHz, V: 75.008 Hz
    geometry 768 576 768 1152 32
    timings 20330 128 32 32 8 128 5
    accel true
    rgba 8/16,8/8,8/0,8/24
endmode

Linux FIle & Media Server

I had several external usb hardisk. I need to bring them along with my laptop when needed. I though why not create a file server, so that i can still access it anywhere at home. Utilizing one of the cubieboard, i create this file server.

Samba Server
sudo apt-get install samba cifs-utils ntfs-3g dosfstools

add these lines at the end of /etc/samba/smb.conf
[media]
 path = /media
 public = yes
 writable = yes
 comment = smb share
 printable = no
 guest ok = yes
 read only = no
 directory mask = 0777

Homemade 3G Router/APCombo

This article show you how to make your own 3g router using embedded linux, in my case i'm using a raspberry pi 1 Model B. What you need other then the board it self were 3g modem and wifi dongle. The Wifi dongle that were gonna use, should have multiple tx queue features, one from atheros should do the trick.

Ethernet/LAN was bridged with Wifi. In this way client via ethernet can also connected to the network. The bridge hold the system ip address, and no ip assigned to ethernet or wifi.

3G connection were done by umtskeeper which include sakis3g, AP were done by hostapd working along with dnsmasq for dhcp and brigde util to configure the network bridge.

Media Player On Allwinner device.

This is my note to make media player that work on Cubieboard, Bananapi and other allwinner board. Assume you already had a working debian wheezy system running on the board.

Add these repository:
sudo vi /etc/apt/source.list
deb http://dl.bananian.org/packages/ wheezy main
deb http://packages.cubian.org/ wheezy main non-free

Add gpg key:
wget -O - http://packages.cubian.org/cubian.gpg.key | sudo apt-key add -
wget -O - http://dl.bananian.org/packages/bananian-packages.key | sudo apt-key add -