Eclypse Z7 Low Level Zmod ADC DAC Demo

The project demonstrates the implementation of a basic signal processing application on the Eclypse platform (Eclypse Z7 + Zmod Scope + Zmod AWG).

The simplified block diagram of the system implemented for this demo is shown below:

reproduce this diagram with different names

An analog input coming from the Analog Discovery 2 (AD2) is connected to the Zmod Scope CH1, converted to a digital format and passed on to the input of a digital low pass filter. The filter's output is converted back to an analog format by the Zmod AWG and can be measured/visualized on the converter channel 1.

The input signal, after the analog to digital conversion, is also looped back to the Zmod AWG and connected to the CH2 output. The Analog Discovery 2's Network Analyzer instrument is then used to plot the frequency characteristic using the CH2 of the Zmod AWG as reference.

The purpose of the digital loopback is to correct the phase errors introduced by the ADC and Zmod Scope Controller latency and the gain errors caused by the mismatch between the ADC and the DAC full scale voltages.

With this setup the frequency response of the filter can be correctly measured regardless of the gain setting of the Zmod AWG.

Only the Zynq’s Programmable Logic (PL) is used for this project.

The IPs instantiated in the design and their functionality are described below:

• The Zmod Scope Controller - initializes the Zmod Scope hardware and synchronizes the incoming data in the user clock domain,
• A digital low pass filter – implemented using Xilinx FIR compiler 7.2 IP Core with the coefficients specified in Table 1, below.
• The Zmod AWG Controller - initializes the Zmod AWG hardware and formats the output data according to the AD9717 DAC requirements.

Table 1. FIR Filter Coefficients

0.0031577,
0.0063382,
0.0117886,
0.0192569,
0.0285887,
0.0393138,
0.0506561,
0.0616162,
0.0711065,
0.0781057,
0.0818212,
0.0818212,
0.0781057,
0.0711065,
0.0616162,
0.0506561,
0.0393138,
0.0285887,
0.0192569,
0.0117886,
0.0063382,
0.0031577.

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• Eclypse Z7
  • Including a Micro-USB cable and 12V Power Supply
• A Zmod Scope, one of the following:
  • Zmod Scope 1010
  • Zmod Scope 1210
  • Zmod Scope 1410
• Zmod AWG 1411
• Analog Discovery 2 (AD2)
• Discovery BNC Adapter

• Vivado Design Suite 2019.1 with Digilent Board Support Files installed
  • Follow the Installing Vivado, Xilinx SDK, and Digilent Board Files guide on how to install Vivado and Digilent Board Support Files.
• Waveforms Software

• Basic familiarity with Vivado
  • This experience can be found by walking through our “Getting Started with Vivado” guide

Advanced users may want to take a look at the branch of Eclypse Z7 repository containing the project.

1. Connect the Analog Discovery 2 board to the host computer using a MicroUSB cable.

2. Connect the Eclypse Z7 board to the host computer using a MicroUSB cable through PROG MicroUSB port and power the board using the 12V Power Supply. Flip its power switch to turn it on.

3. Connect the two Zmods, Scope and AWG, to the Zmod connectors of the Eclypse Z7 board as follows:

• Zmod Scope to ZMOD A connector of the Eclypse Z7
• Zmod AWG 1411 to ZMOD B connector of the Eclypse Z7

4. Connect the BNC adapter to the Analog Discovery 2

5. Make the following physical connections:

• Analog Discovery 2 Waveform Generator channel 1 (W1) to Zmod Scope CH1
• Zmod AWG CH1 to Analog Discovery 2 Oscilloscope channel 2 (CH2)
• Zmod AWG CH2 to Analog Discovery 2 Oscilloscope channel 1 (CH1)

Note: Since the Zmods use SMA connectors, use of BNC-to-SMA cables (or BNC-to-SMA adapters with BNC or SMA cables) is recommended for the Zmod to BNC Adapter physical connections.

1. Download and extract the Vivado project archive, linked in the Downloads section, above. Open the project in Vivado.

If you are using a variant of the Zmod Scope other than the 1410-105, check the following dropdown for instructions on modifying the project to support your Zmod and rebuilding it.

FIXME

2. Download and extract the WaveForms workspace, linked in the Downloads section, above.

3. Make sure the boot mode jumper on the Eclypse Z7 is in the JTAG position.

4. Open the Hardware Manager tool from within Vivado and click Open target, Autoconnect:

5. Select the .bit file, or make sure it is already selected and is located at the correct path in the dialog (the bit file can be found in the project at hw.runs/impl_1/design_1_wrapper.bit), and program the board.

6. Open WaveForms, then open the workspace, “EclypseZ7VhdlFilterDemo.dwf3work”, included in the folder extracted from the demo archive.

Hit the Run button of the Network Analyzer instrument.

The Network Analyzer will be used to generate a sinusoidal signal (perturbation) on the W1 channel. The bode plot (see below) is obtained considering the loopback signal (Zmod AWG CH2) as reference.

For more guides and example projects for your Eclypse Z7, please visit its Resource Center.

For more information about how to use the other Digilent products featured in this demo, please visit their respective Resource Centers:
Analog Discovery 2, BNC Adapter, Zmod Scope Resource Center (Redirect), Zmod AWG Resource Center (Redirect).

For technical support, please visit the Digilent Forums.