Raspberry Pi vs. Next-Big-Thing's CHIP SoC Computer

Feature	RPI 1 Model A	RPI 1 Model B	RPI 1 Model A+	RPI 1 Model B+	RPI 2ModelB	NBT CHIP
SoC	BRCM 2835	BRCM 2835	BRCM 2835	BRCM 2835		AllWinner's R8
Standard SoC Speed (MHz)	700	700	700	700	900	1000
RAM (MB)	256	512	256	512		512
Ethernet (Mbps)	N/A	100	100	100	1000	N/A
HDMI output	N/A	Yes	Yes	Yes	Yes	With extra module
Composite Video out	Yes	Yes	via 3.5 mm jack	via 3.5 mm jack	via 3.5 mm jack	Yes
Number of USB2.0	2	2	1	4	4	1
CPU Cores	1	1	1	1	4	1
Storage	SD Card	SD Card	micro SD	micro SD	MicroSD	Built-in Flash
Internal Storage Capacity	N/A	N/A	N/A	N/A	N/A	4 MB
Camera Interface (CSI)		yes	yes	yes	yes	yes
Display Interface (DSI)		yes	yes	yes	yes	yes
Video/Graphic Coprocessor	VideoCore IV	VideoCore IV	VideoCore IV	VideoCore IV	VideoCore IV	PowerVR SGX544
Architecture	ARM11v6	ARM11v6	ARM11v6	ARM11v6	ARMv7	ARMv7
GPIO Pins	26	40	40	40	40

OpenFrameworks: Another cool Multi-platform Framework for Graphics

Steps to download and build OpenFrameWorks:

• git clone https://github.com/openframeworks/openFrameworks.git
• goto the OF root.  This is usually the folder openFrameworks.  Change directory to ./scripts/linux/ubuntu (e.g: cd openFrameworks/scripts/linux/ubuntu)

• Execute the scripts in the folder as root:

sudo ./install_dependencies.sh

sudo ./install_codecs.sh

Go to ./scripts/linux and execute:

./compileOF.sh
./compilePG.sh

To generate projects (Makefile etc.)  for all the examples, goto OF root, then type:

projectGenerator -v -r examples/

wxWidgets 3.0

To add the repository, first import the key:

sudo apt-key adv --fetch-keys http://repos.codelite.org/CodeLite.asc

Then add the source:

sudo tee /etc/apt/sources.list.d/wxwidgets.list
deb http://repos.codelite.org/wx3.0.2/ubuntu/  $(lsb_release -sc) universe
sudo apt-get update

Install wxWidgets modules:

sudo apt-get install libwxbase3.0-0-unofficial libwxbase3.0-dbg libwxbase3.0-dev libwxgtk3.0-0-unofficial libwxgtk3.0-dbg wx3.0-doc wx3.0-examples 

Create soft-link:

sudo ln -s /usr/include/wx-3.0-unofficial/wx /usr/include/wx 

To compile a single file, create a script named wxcompile and edit it with the content as below (assume with have subdirectory obj/Debug and bin/Debug:

#!/bin/bash

if [ -z "${1}" ]
then
    echo "$0 "
    exit 1
fi

FILE=`basename $1`
CPPF=$FILE
OBJF=`basename -s .cpp $CPPF`
OBJF=${OBJF}.o
g++ -g -c -Wall -DWX_PRECOMP -Winvalid-pch `wx-config --cppflags` -o obj/Debug/${OBJF} ${CPPF}

To link, create a script file name 'wxlink' and its content as below:

#!/bin/bash

if [ -z "${1}" ]
then
    echo "$0 "
    exit 1
fi

FOUT=$1
OBJF=obj/Debug/*.o

g++ -v obj/Debug/*.o `wx-config --libs` -o obj/Debug/$FOUT

For a bigger project which requires more complicated and conditional compilation, use Makefile.

Watching Nabawi-TV via VLC on Raspberry Pi

A new Indonesian da'wah TV has provided a streaming.

To watch, install vlc.  Once installed, open the VLC, click "Media", and then "Open Network Stream".  Enter:

rtsp://wowza60.indostreamserver.com:1935/nabawitv/live

Script to simulate multiple DHCP clients

#!/bin/sh

#simulate 255 IPhones requesting DHCP

 

 

# Apple OUI = D8:96:95

BASE="d8:96:95:08:96"

FROM=$1

shift

TO=$2

 

if [ -e $FROM ]; then FROM=1; fi

if [ -e $TO ]; then TO=1; fi

 

for i in `seq $FROM $TO`

do

    LSB=`echo "obase=16; $i" | bc`

    MAC="$BASE:$LSB"

    HNAME="`uname -n`-fakehost-$i"

    #CMD="$HOME/bin/dhtest -m $MAC -V -i eth1 -h '$HNAME'"

    CMD="$HOME/bin/dhtest -m $MAC -i eth1 -h '$HNAME'"

    echo $CMD

    $CMD

    sleep 1

done

Another way, the program dhtest (source code) can be download from  https://github.com/saravana815/dhtest.  

For example:

 

git clone https://github.com/saravana815/dhtest

cd dhtest

make

Daily backup of local git changes

While working on a ticket and not ready to commit, it's a good idea to backup all of our changes to an archive file.

The following script does all that and executed daily by cronjob automatically.

1. create a file, say "backup" in /etc/cron.daily
2. Type the following (change '<yourhome directory>' to your own login name and <git location> to the git directory where source codes are located):

backing up changed files to tarball

#!/bin/sh pushd <your source-code location> LIST=`git status --porcelain | sed -n -e '/^ [D|M]/p' | sed -e 's/^ [D|M] //'` backupname=`git branch | sed -n -e "/^* /p" | sed  -e 's/** //'` backupname=$backupname-`date "+%s"`.backup.tar.bz2 dest='<your home directory>' if [ ! -d "$dest" ] then     mkdir -p $dest fi tar jcvf $dest/$backupname $LIST > /dev/null

Make the file executable:

chmod +x /etc/cron.daily/backup