Programming Category - Page 39 of 43 - CNX Software

April 29, 2011August 23, 2018 by Jean-Luc Aufranc (CNXSoft) - 8 Comments

Yocto Project: Build Your Own Custom Embedded Kernel Image

The Yocto Project is an open source collaboration project that provides templates, tools and methods to help you create custom Linux-based systems for embedded products regardless of the hardware architecture. The first official release (Yocto Project 1.0) has been made available on the 6th of April 2011. Yocto Project Overview See this short video presentation of the Yocto Project which explains its goals. It’s a complete embedded Linux development environment with tools, metadata, and documentation – everything you need such as emulation environments, debuggers, an Application Toolkit Generator, etc… It is not a new build system however such as buildroot, instead it relies on the Poky build tools that provide an open source development environment targeting the ARM, MIPS, PowerPC and x86 architectures. Here’s what the Yocto Project provides: A recent Linux kernel along with a set of system commands and libraries suitable for the embedded environment. System components such […]

April 28, 2011February 22, 2015 by Jean-Luc Aufranc (CNXSoft) - No Comments

Qualcomm Officially Releases its Augmented Reality SDK

Qualcomm has just released the official release of their Augmented Reality SDK with Unity 3.0 Support: Qualcomm Incorporated (NASDAQ: QCOM) today announced the immediate commercial availability of its Augmented Reality (AR) Platform for Android smartphones. Offered through Qualcomm’s online developer network, this 1.0 release marks the successful completion of the Company’s beta program. Developers can now build, market and commercially distribute applications based on the Qualcomm AR platform. … The platform supports multiple development environments. The Qualcomm AR Android SDK supports native Android development with the Android tool chain, including the Android SDK and NDK. The Qualcomm AR Unity Extension supports rapid development with the Unity 3 game development tool. A web application is also included for creating and managing image resources that can be used with either development environment. You may have check out the complete QCAR SDK Press Release. You can download the the latest Qualcomm SDK and […]

April 22, 2011April 22, 2011 by Jean-Luc Aufranc (CNXSoft) - No Comments

Compile with ARM Thumb2 to Reduce Memory Footprint and Improve Performance

ARM claims that Thumb-2 instructions (for ARM Cortex cores and all ARMv7 processors) provides performance improvements and code size optimization: Thumb-2 technology is the instruction set underlying the ARM Cortex architecture which provides enhanced levels of performance, energy efficiency, and code density for a wide range of embedded applications. For performance optimized code Thumb-2 technology uses 31 percent less memory to reduce system cost, while providing up to 38 percent higher performance than existing high density code, which can be used to prolong battery-life or to enrich the product feature set. Thumb-2 technology is featured in the processor, and in all ARMv7 architecture-based processors. Dave Martin (Linaro) has recently posted a message entitled “ARM/Thumb-2 kernel size comparison” on Linaro mailing list:

The question of the size impact of building the kernel in Thumb-2 came
up to day, so I extracted some quick numbers:

$ size vmlinux-*
text	   data	    bss	    dec	    hex	filename
8420507	 463356	 826928	9710791	 942cc7	vmlinux-arm
6715539	 463260	 826928	8005727	 7a285f	vmlinux-thumb2

This is for a recent mainline kernel built with the linaro omap config.

In this case we save about 20% for code and read-only data (i.e.,
text) and 17.5% overall -- which accounts for a little under 2MB saved
in this example.

This doesn't take loadable modules into account; we can probably expect
to see a similar size ratio there.

The question of the size impact of building the kernel in Thumb-2 came

up to day, so I extracted some quick numbers:

$ size vmlinux-*

text data bss dec hex filename

8420507 463356 826928 9710791 942cc7 vmlinux-arm

6715539 463260 826928 8005727 7a285f vmlinux-thumb2

This is for a recent mainline kernel built with the linaro omap config.

In this case we save about 20% for code and read-only data (i.e.,

text) and 17.5% overall -- which accounts for a little under 2MB saved

in this example.

This doesn't take loadable modules into account; we can probably expect

to see a similar size ratio there.

The results provided by Linaro at not as high as those claimed by ARM, but a 20% code size reduction is still impressive. If you want to use Thumb2 to compile […]

April 19, 2011April 19, 2011 by Jean-Luc Aufranc (CNXSoft) - No Comments

Embedded Linux Quick Start / Tutorial Videos

Free Electrons recorded some videos from the Embedded Linux Conference Europe, in Cambrigde, United Kingdom on October 2010 by Chris Simmonds, the founder of 2net Limited, a UK company providing training, consultancy and custom software for Linux and other embedded platforms. The videos can either be downloaded in webm HD format at http://free-electrons.com/blog/elce-2010-tutorial-videos/ or you can watch them in HD format below. The PDF slides for the three parts and the lab notes are available at http://elinux.org/images/c/cc/Linux-quick-start.tar.gz The first video (53 minutes) deals with the following key points: Genesis of a Linux project The four elements: Tool chain; boot loader; kernel; user space Element 1: Tool chain Element 2: Boot loader The second video (1h19m) focuses on: Third element: Kernel Fourth element: User space The last video (1h07m) is more practical as it shows how to use embedded Linux on an NXP LPC3250 Stick (ARM9): Description of the hardware Installing […]

April 5, 2011 by Jean-Luc Aufranc (CNXSoft) - No Comments

C Code to get MAC Address and IP Address

Function in C to return the MAC Address:

/* Returns the MAC Address
   Params: int iNetType - 0: ethernet, 1: Wifi
           char chMAC[6] - MAC Address in binary format
   Returns: 0: success
           -1: Failure
    */
int getMACAddress(int iNetType, char chMAC[6]) {
  struct ifreq ifr;
  int sock;
  char *ifname=NULL;

  if (!iNetType) {
    ifname="eth0"; /* Ethernet */
  } else {
    ifname="wlan0"; /* Wifi */
  }
  sock=socket(AF_INET,SOCK_DGRAM,0);
  strcpy( ifr.ifr_name, ifname );
  ifr.ifr_addr.sa_family = AF_INET;
  if (ioctl( sock, SIOCGIFHWADDR, &amp;ifr ) &lt; 0) {
    return -1;
  }
  memcpy(chMAC, ifr.ifr_hwaddr.sa_data, 6)
  close(sock);
  return 0;
}

/* Returns the MAC Address

Params: int iNetType - 0: ethernet, 1: Wifi

char chMAC[6] - MAC Address in binary format

Returns: 0: success

-1: Failure

int getMACAddress(int iNetType, char chMAC[6]) {

struct ifreq ifr;

int sock;

char *ifname=NULL;

if (!iNetType) {

ifname="eth0"; /* Ethernet */

} else {

ifname="wlan0"; /* Wifi */

}

sock=socket(AF_INET,SOCK_DGRAM,0);

strcpy( ifr.ifr_name, ifname );

ifr.ifr_addr.sa_family = AF_INET;

if (ioctl( sock, SIOCGIFHWADDR, &ifr ) < 0) {

return -1;

}

memcpy(chMAC, ifr.ifr_hwaddr.sa_data, 6)

close(sock);

return 0;

}

Function in C to return the IP Address:

/* Returns the interface IP Address
   Params: int iNetType - 0: ethernet, 1: Wifi
           char *chIP - IP Address string
   Return: 0: success / -1: Failure
    */
int getIpAddress(int iNetType, char chIP[16]) {
  struct ifreq ifr;
  int sock = 0;

  sock = socket(AF_INET, SOCK_DGRAM, 0);
  if(iNetType == 0) {
    strcpy(ifr.ifr_name, "eth0");
  } else {
    strcpy(ifr.ifr_name, "wlan0");
  }
  if (ioctl(sock, SIOCGIFADDR, &amp;ifr) &lt; 0) {
    strcpy(chIP, "0.0.0.0");
    return -1;
 }
 sprintf(chIP, "%s", inet_ntoa(((struct sockaddr_in *) &amp;(ifr.ifr_addr))-&gt;sin_addr));
 close(sock);
 return 0;
}

/* Returns the interface IP Address

Params: int iNetType - 0: ethernet, 1: Wifi

char *chIP - IP Address string

Return: 0: success / -1: Failure

int getIpAddress(int iNetType, char chIP[16]) {

struct ifreq ifr;

int sock = 0;

sock = socket(AF_INET, SOCK_DGRAM, 0);

if(iNetType == 0) {

strcpy(ifr.ifr_name, "eth0");

} else {

strcpy(ifr.ifr_name, "wlan0");

}

if (ioctl(sock, SIOCGIFADDR, &ifr) < 0) {

strcpy(chIP, "0.0.0.0");

return -1;

}

sprintf(chIP, "%s", inet_ntoa(((struct sockaddr_in *) &(ifr.ifr_addr))->sin_addr));

close(sock);

return 0;

}

Jean-Luc Aufranc (CNXSoft)Jean-Luc started CNX Software in 2010 as a part-time endeavor, before quitting his job as a software engineering manager, and starting to write daily news, and reviews full time later in 2011. www.cnx-software.com

March 28, 2011 by Jean-Luc Aufranc (CNXSoft) - 19 Comments

Installing Linaro ARM Cross Toolchain on Ubuntu

You can easily install Linaro arm cross-compiler on Ubuntu 10.04 (Lucid), 10.10 (Maverick) and 11.04 (Natty) as follows: sudo apt-get install gcc-arm-linux-gnueabi This will install Linaro cross-toolchain version 4.4 on Ubuntu 10.04 and 10.10, and version 4.5 on Ubuntu 11.04. You can check the installation worked by checking the cross-compiler version jaufranc@CNX-TOWER:~$ arm-linux-gnueabi-gcc -v Using built-in specs. Target: arm-linux-gnueabi Configured with: ../src/configure -v –with-pkgversion=’Ubuntu/Linaro 4.4.4-14ubuntu4′ –with-bugurl=file:///usr/share/doc/gcc-4.4/README.Bugs –enable-languages=c,c++,fortran,objc,obj-c++ –prefix=/usr –program-suffix=-4.4 –enable-shared –enable-multiarch –enable-linker-build-id –with-system-zlib –libexecdir=/usr/lib –without-included-gettext –enable-threads=posix –with-gxx-include-dir=/usr/arm-linux-gnueabi/include/c++/4.4.5 –libdir=/usr/lib –enable-nls –enable-clocale=gnu –enable-libstdcxx-debug –enable-objc-gc –disable-sjlj-exceptions –with-arch=armv7-a –with-float=softfp –with-fpu=vfpv3-d16 –with-mode=thumb –disable-werror –enable-checking=release –program-prefix=arm-linux-gnueabi- –includedir=/usr/arm-linux-gnueabi/include –build=i686-linux-gnu –host=i686-linux-gnu –target=arm-linux-gnueabi –with-headers=/usr/arm-linux-gnueabi/include –with-libs=/usr/arm-linux-gnueabi/lib Thread model: posix gcc version 4.4.5 (Ubuntu/Linaro 4.4.4-14ubuntu4) You can also install the latest version 4.5 (recommended) on Lucid and Maverick: sudo add-apt-repository ppa:linaro-maintainers/toolchain sudo apt-get update sudo apt-get install gcc-4.5-arm-linux-gnueabi If you are using an ARM platform running Ubuntu 10.10 or higher, you could also use the native GCC compiler. sudo apt-get install […]

March 21, 2011August 19, 2011 by Jean-Luc Aufranc (CNXSoft) - 8 Comments

Cross compiling Berkeley DB for ARM and MIPS

Following my blog entry about Databases for Linux Embedded Systems, here are the instructions to cross-compile Oracle Berkeley DB. First download the source code of the latest version of Berkeley DB (version 11gR2 – 11.2.5.1.25). You’ll need to register on Oracle website first on the download page http://www.oracle.com/technetwork/database/berkeleydb/downloads/index.html to download http://download.oracle.com/otn/berkeley-db/db-5.1.25.tar.gz (with AES encryption) or http://download.oracle.com/otn/berkeley-db/db-5.1.25.NC.tar.gz (if you don’t need encryption). Extract the source code: tar xzvf ../Downloads/db-5.1.25.tar.gz Configure and build the source code. I’ll use mipsel-linux-gcc, but any other cross-compiler could be used. cd db-5.1.25/build_unix ../dist/configure –host=mipsel-linux CC=mipsel-linux-gcc RANLIB=mipsel-linux-ranlib STRIP=mipsel-linux-strip AR=mipsel-linux-ar –prefix=/home/jaufranc/edev/lib/db-11g make make install The full berkeley DB package is 79MB: jaufranc@CNX-TOWER:~/edev/lib/db-11g$ du –max-depth=1 -h 6.6M ./lib 308K ./bin 72M ./docs 176K ./include 79M . However, you won’t need the include and docs directory in your embedded target. So you do not need to copy those. You may or may need the utilities in the bin file. The […]

March 14, 2011May 2, 2012 by Jean-Luc Aufranc (CNXSoft) - 3 Comments

Cross compiling SQLite for ARM and MIPS

Following my blog entry about Databases for Linux Embedded Systems, here are the instructions to cross-compile SQlite. First download the latest version of SQLite amalgamation with autoconf script (version 3.75): wget http://www.sqlite.org/sqlite-autoconf-3070500.tar.gz Extract the source code: tar xzvf sqlite-autoconf-3070500.tar.gz Configure and build the source code. I’ll use mipsel-linux-gcc, but any other cross-compiler could be used. cd sqlite-autoconf-3070500 ./configure –host=mipsel-linux –target=mipsel-linux –prefix=/home/jaufranc/edev/sqlite-mips make make install At this point the library is correctly configured and installed, so you’d just need to copy the relevant files to your target board (skip include and share directories and libsqlite3.a) . Let’s check the size of the required files: ls -l ../sqlite-mips/bin/ -rwxr-xr-x 1 jaufranc jaufranc 125513 2011-03-14 14:21 sqlite ls -l ../sqlite-mips/lib/libsqlite3.so.0.8.6 -rwxr-xr-x 1 jaufranc jaufranc 2087584 2011-03-14 14:21 ../sqlite-mips/lib/libsqlite3.so.0.8.6 sqlite binary is 122.57KB and the dynamic library 2038.65KB. Let’s see if we can optimize the binary size with compilation flags and by disabling some […]