Run the Demonstration Remotely via Ethernet (AD7768)

In addition to the DataStorm DAQ development kit running in standalone mode, it can also run while connected to computer remotely via an Ethernet cable.

Configuration for remote IIO Oscilloscope access via ethernet

The AD7768® Evaluation Platform in this configuration is comprised of the following components: The AD7768 Evaluation Platform in this configuration is comprised of the following components:

• Analog Devices EVAL-AD7768FMCZ data converter board
• Trenz Intel Cyclone V SoC TEI0022 Development Board (includes 12VDC power supply)
• Computer with IIO Oscilloscope installed
• Ethernet Cable
• Micro USB cable
• Signal Generator with dual outputs capable of channel tracking and inversion for differential outputs
• Two (2) BNC to SMB Cables

Assemble the Hardware

Follow the steps in the order shown below.

• Insert the Micro SD card into the SD card slot
• Insert the EVAL-AD7768FMCZ FMC connector into the FMC mating connector on the Trenz TEI0022 board
• Attach PC via ethernet cable
• Attach the Micro USB cable
• Connect the Signal Generator to the EVAL-AD7768FMCZ SMA connectors (channel 0)
• Ensure that Jumper LK1 is in position B and LK2 is in position A on the EVAL-AD7768 board, for it to be powered via the FMC connector

• Connect the power supply to the TEI0022
• Plug the AC-DC adapter into an AC outlet

Signal Source

A signal generator with 2 outputs is used to generate the differential signals driving the AD7768 inputs. The AD7768 expects the input signals to swing between AVSS and AVDD1. This means that the user is expected to provide a true differential input centered at VCOM (AVDD1-AVSS)/2.

• Set up the first channel to generate the desired signal
• Set up the second channel for tracking the first channel
• Offset both channels with VCOM.

Software for remote IIO Oscilloscope access via ethernet

There are a few software components that need to be installed in order to run this demo successfully:

1. IIO Oscilloscope™
2. A SW terminal like Tera Term VT or Putty

IIO Oscilloscope™

IIO Oscilloscope™ is a tool developed by Analog Devices. It can be downloaded for Windows or Linux from this web site: https://github.com/analogdevicesinc/iio-oscilloscope/releases (Download and install v0.13)

Define the host PC IP address

A wired ethernet point-to-point connection between the host PC and the embedded target is required. Use this link for instructions on how to assign a static IP address to the host Ethernet adapter. Set the following values

• IP address : 192.168.0.1

• Subnet mask : 255.255.255.0

• No entries required for the other fields

Connect to the target terminal

• A wired Micro USB serial port connection between the host PC and the embedded target is required
• Launch a linux terminal (like Tera Term VT or Putty) and connect using serial port
• Select 115200 baud
• Select the appropriate target COM port

Define the target IP address

Type the following at the terminal prompt to set the target IP address

• $ ifconfig eth0 192.168.0.2 up

Launch IIO Oscilloscope

Note: IIO Oscilloscope creates a .osc_profile.ini file in the Users/UserName/Appdata/Local directory. The next time IIO Oscilloscope is opened, the existence of this file delays connection to the target. It is recommended to delete the .osc_profile.ini (if it exists) prior to launching IIO Oscilloscope.

Connect to the target

• Select the Discoverable/Scan option and click the Refresh button..
• A successful connection results in discovery of the IIO devices. Press OK to continue.

Enable voltage0 ADC channel

Select a Plot Channel to be displayed in IIO Oscilloscope. Click on the check box in the Plot Channel window adjacent to voltage0. Right click on axi-ad7768-adc in the Plot Channels window. Select voltage0 and rising edge as the trigger parameters.

Capture Time Domain Signals

Press the Capture / Stop button to begin the capture process.

Capture Frequency Domain Signals with Frequency Markers enabled

Change the capture mode to Frequency Domain. Select an FFT Size and Average. Press the Capture / Stop button to begin the capture process.

Right click in the IIO Oscilloscope plot area. Select Single Tone markers. Press the Capture / Stop button to begin the capture process with markers.

Note the information in the Marker window. This capture shows a signal source of 10 khz with harmonic components.

Software for the Python demonstration

There are a few software components that need to be installed in order to run this demonstration successfully:

Install Python 3.7

• Download Python 3.7 and run the installer

• A typical installation location will be C:\Users\username\AppData\Local\Programs\Python

• Edit the Windows System PATH environment variable to add the path to the Python directory

• Edit the Windows System PATH environment variable to add the path to the Python\Scripts directory

Install PIP

• Use the following instructions to install PIP

Install LibIIO - API library for IIO

• Download and run the LibIIO installer

Install PyADI-IIO and matplotlib

• Open a CMD shell.

    > pip install pyadi-iio
    > python -m pip install -U matplotlib
  

Run the Python script

The LibIIO library API enables access to the converter data from C code, Python code, or Matlab. A small sample of Python code is provided for the reader and can be run natively on the DataStorm DAQ.

Download Python source code

• Download the python source code from the github repository

• Run the Python source code. Open a CMD shell

    $ python3 ad7768evb.py
  

Shutting down the demo

• Power down the target. Type the following at the terminal prompt

    $ poweroff  
  

• Wait until the linux terminal shows

    $ reboot : System Halted
  

• Close out IIO Oscilloscope and all associated windows

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