Table of Contents

Network Scope Project

Introduction

This document explains how to install and build the Network Scope Project, beginning with an already existing uClinux Distribution on your development host computer. Supported Hosts are any native Unix/Linux system, approved to compile the uClinux kernel, and systems based on the Blackfin CoLinux uClinux Distribution for the Windows™ platform (available atblackfin.uclinux.org). The Network Scope allows you to learn about and evaluate uClinux on Analog Devices Inc. Blackfin™ family based processors. Even if the system is accurate, its practical use is not quite obvious, since most of us have more ambitious Scopes on the table. As you deploy the systems, think about how you can use it in your application. Things to learn are remote access and administration, process data visualization and presentation for embedded systems. In addition to that, integration of existing open source based programs and applications to suit your applications needs, can be learned by comparing it with the officially based distributions.

The following will guide you through a multistep installation procedure

  1. Prerequisites
  2. Building the Network Scope
  3. Starting the Network Scope

Overview

The Network Scope, demonstrates a simple mechanism to share access and data distributed over a TCP/IP network. The web browser contacts the HTTP server running on Blackfin where the CGI script or program resides, and asks it to run the program. Parameters from the HTML form are passed to the program (parameters are passed through the Environment, or passed similar to command line arguments) The called program samples data from the ADC using a linux device driver (adsp-spiadc.c). Incoming samples are preprocessed and stored in a file. The CGI program then calls Gnuplot and requests to generate a PNG or JPEG image based on the sampled data and form settings. (Gnuplot is a portable command-line driven interactive datafile and function plotting utility). The server takes the output of the CGI program and returns it to the web browser. The web browser displays the output as an HTML page.

Prerequisites

You'll need at least the following hardware:

Optionally, you can have:

For information on where to acquire these parts, please see our buy stuff page.

All of the required software is part of our uClinux-dist release.

Building the Network Scope

In the main uClinux directory, run:

make menuconfig

Then enable vendor/kernel customizations:

Kernel/Library/Defaults Selection  --->
  [*] Customize Kernel Settings
  [*] Customize Vendor/User Settings

In the kernel configuration menu, you will need to enable these options:

Device Drivers  --->
  Character devices  --->
    [*] Blackfin BF53x ADSP SPI ADC support

In the vendor/user configuration menu, you will need to enable these options:

Library Configuration  --->
  [*] Build libZ
  [*] Build libpng

Blackfin canned demos  --->
  [*] Networked Software Defined Storage Oscilloscope

Starting the Network Scope

Open a web browser and enter the IP-Address you assigned to the STAMP board.

Form Options

— Trigger Options:
The left drop down field enables or disables the Trigger. The right field provides options for Level or Edge sensitive triggers. Options are Rising and Falling Edge triggers. The Level Textbox is used to adjust the desired trigger level. Maximum level is 4096 mV.

— Vertical:
Fine control of the major (labeled) tics on the y axis.

— Sample Frequency:
Recommended Sample Frequency measured in SPS (samples per second). The actual sample frequency may vary, due to divide ratios of System Clock. However the actual Sample frequency is displayed and used to scale the plot. Maximum Sample frequency for the AD7476A ADC is 1MSPS.

— Depth:
Number of samples to be sampled

— Range:
This option specifies the region of the graph that will be displayed. A * can be used to allow autoscaling of either of min and max.

— Grid:
The grid option allows grid lines to be drawn on the plot.

— Highlight Zeroaxis:
This option allows the Zeroaxis to be drawn on the plot.

— Size Ratio:
The Size Ratio option scales the displayed size of the plot. The size is relative to the default size. Example: To make the graph twice as high as wide use: 2 or 2.0

— Time/Frequency Domain:
Decides whether the plot is displayed in Time/Frequency Domain. In case of Frequency the FFT options below are enabled.

— FFT:
Select the FFT size, available options are 1024, 512, 256, 128, 64, 32 and 16. Entries in the Horizontal Depth field are ignored.

— Scaled:
Removes redundant information and scales the plot on the frequency axis according to the Sample Frequency.

— Exclude F(0):
Excludes the DC part from being plotted.

— Plot Style:
Available options are: lines points, points, dots, lines, impulses, fsteps, histeps, boxes, steps.

— Scale:
Logarithmic scaling can be enabled on the horizontal and vertical or both axis.

— Interpolate:
These options include a few general-purpose routines for interpolation and approximation of data.

— Measurements:
If checked these options perform calculation of statistical outputs.

— Input:
Set to AC in when the AD7476-DBRD is jumpered for AC input mode.

— Show on Frame Buffer:
If you have a LCD attached to the PPI and the framebuffer driver is loaded, then this option will tell the system to output the requested image to the LCD device as well.


Action Buttons

— Acquire:
Samples data and plots it based on the current form settings.

— Replot:
Replots previous sampled data, based on the current form settings.

— Multimeter:
Displays current input voltage.

— Show Samples:
Displays the sampled data in MATLAB and C array declaration.

— Files:
Opens a dynamically generated webpage page, providing links to view the gnuplot files, generated by the Network Scope.

— Default:
Resets the form settings to it’s default state.