New Horizons

Welcome to my blog

My name is Sven Andersson and I
work as a consultant in embedded
system design, implemented in ASIC
and FPGA.
In my spare time I write this blog
and I hope it will inspire others to
learn more about this fantastic field.
I live in Stockholm Sweden and have
my own company


You are welcome to contact me
and ask questions or make comments
about my blog.


New Horizons
What's new
Starting a blog
Writing a blog
Using an RSS reader

Zynq Design From Scratch
Started February 2014
1 Introduction
Changes and updates
2 Zynq-7000 All Programmable SoC
3 ZedBoard and other boards
4 Computer platform and VirtualBox
5 Installing Ubuntu
6 Fixing Ubuntu
7 Installing Vivado
8 Starting Vivado
9 Using Vivado
10 Lab 1. Create a Zynq project
11 Lab 1. Build a hardware platform
12 Lab 1. Create a software application
13 Lab 1. Connect to ZedBoard
14 Lab 1. Run a software application
15 Lab 1. Benchmarking ARM Cortex-A9
16 Lab 2. Adding a GPIO peripheral
17 Lab 2. Create a custom HDL module
18 Lab 2. Connect package pins and implement
19 Lab 2. Create a software application and configure the PL
20 Lab 2. Debugging a software application
21 Running Linux from SD card
22 Installing PetaLinux
23 Booting PetaLinux
24 Connect to ZedBoad via ethernet
25 Rebuilding the PetaLinux kernel image
26 Running a DHCP server on the host
27 Running a TFTP server on the host
28 PetaLinux boot via U-boot
29 PetaLinux application development
30 Fixing the host computer
31 Running NFS servers
32 VirtualBox seamless mode
33 Mounting guest file system using sshfs
34 PetaLinux. Setting up a web server
35 PetaLinux. Using cgi scripts
36 PetaLinux. Web enabled application
37 Convert from VirtualBox to VMware
38 Running Linaro Ubuntu on ZedBoard
39 Running Android on ZedBoard
40 Lab2. Booting from SD card and SPI flash
41 Lab2. PetaLinux board bringup
42 Lab2. Writing userspace IO device driver
43 Lab2. Hardware debugging
44 MicroZed quick start
45 Installing Vivado 2014.1
46 Lab3. Adding push buttons to our Zynq system
47 Lab3. Adding an interrupt service routine
48 Installing Ubuntu 14.04
49 Installing Vivado and Petalinux 2014.2
50 Using Vivado 2014.2
51 Upgrading to Ubuntu 14.04
52 Using Petalinux 2014.2
53 Booting from SD card and SPI flash
54 Booting Petalinux 2014.2 from SD card
55 Booting Petalinux 2014.2 from SPI flash
56 Installing Vivado 2014.3

Chipotle Verification System

EE Times Retrospective Series
It all started more than 40 years ago
My first job as an electrical engineer
The Memory (R)evolution
The Microprocessor (R)evolution

Four soft-core processors
Started January 2012
Table of contents
OpenRISC 1200
Nios II

Using the Spartan-6 LX9 MicroBoard
Started August 2011
Table of contents
Problems, fixes and solutions

FPGA Design From Scratch
Started December 2006
Table of contents
Acronyms and abbreviations

Actel FPGA design
Designing with an Actel FPGA. Part 1
Designing with an Actel FPGA. Part 2
Designing with an Actel FPGA. Part 3
Designing with an Actel FPGA. Part 4
Designing with an Actel FPGA. Part 5

A hardware designer's best friend
Zoo Design Platform

Installing Cobra Command Tool
A processor benchmark

Porting a Unix program to Mac OS X
Fixing a HyperTerminal in Mac OS X
A dream come true

Stockholm by bike

The New York City Marathon

Kittelfjall Lappland

Tour skating in Sweden and around the world
Wild skating
Tour day
Safety equipment
A look at the equipment you need
Skate maintenance
Books, photos, films and videos
Weather forecasts

38000 feet above see level
A trip to Spain
Florida the sunshine state

Photo Albums
Seaside Florida
Ronda Spain
Sevilla Spain
Cordoba Spain
Alhambra Spain
KittelfjÀll Lapland
Landsort Art Walk
Skating on thin ice

100 Power Tips for FPGA Designers

Adventures in ASIC
Computer History Museum
Design & Reuse
d9 Tech Blog
EDA Cafe
EDA DesignLine
Eli's tech Blog
FPGA Arcade
FPGA Central
FPGA developer
FPGA Journal
FPGA World
Lesley Shannon Courses
Mac 2 Ubuntu
Programmable Logic DesignLine
World of ASIC

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Tuesday, November 22, 2011
FPGA design from scratch. Part 82

Building a web-enabled application

Web serving embedded applications become a lot more useful when the web interface can be used to control the device, or monitor sensor inputs. In this step, we will build and experiment with a simple web-enabled application controlling the LEDs on the LX9 MicroBoard.

Create a new application


--> petalinux-new-app ControlLEDs

Using a CGI script

The Common Gateway Interface (CGI) is a standard method for web servers software to delegate the generation of web pages to executable files. Such files are known as CGI scripts; they are programs, often stand-alone applications, usually written in a scripting language. Our cgi-script is written in c and consists of a number of c program files. The package can be download from here. After unzipping, unpacking and copying the files to the apps directory it looks like this:

Enable the new application

We will enable the ControlLEDs application and disable the TourSkating application.


--> petalinux-config-apps

Build a new image

Compile the application and update the PetaLinux image by running:

--> $PETALINUX/software/petalinux-dist

--> make all romfs image

Booting the new image

This time we will boot the hardware board. For more information see part 76.

1. First bootstrap the system by downloading u-boot via JTAG.

--> cd $PETALINUX/software/petalinux-dist

--> petalinux-jtag-boot -i images/u-boot.elf

2. After u-boot boots, in the console check whether the TFTP server IP address is set to the IP Address of the host where the image resides.

3. Use the command /sbin/ifconfig to find the IP address.

4. In the PetaLinux console type 

--> u-boot> print serverip

5. If not set, set the server IP addreess to the host IP address.

--> u-boot> set serverip <HOST IP ADDRESS>

6. Run netboot to download the PetaLinux image with the TFTP and boot it.

--> u-boot> run netboot

Start the httpd service

Login to the board and start httpd:

# httpd -p 8080 -h /home/httpd

Files in httpd directory

The led.cgi script can be found in the cgi-bin directory.

Controlling hardware from the web browser

We can now control the LEDs on the LX9 MicroBoard from our webbrowser.

  1. Open the web browser
  2. Enter the webaddress: <IP address of the board>:8080/cgi-bin/led.cgi
  3. CGI Blinkenlight will open
  4. Enter the LED GPIO ID. In our case it is 252
  5. Click the ON/OFF links to turn on/off the LEDs on the board

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