Table of Contents
AD5781 FMC-SDP Interposer & Evaluation Board / Xilinx KC705 Reference Design
Supported Devices
Evaluation Boards
Overview
This document presents the steps to setup an environment for using the EVAL-AD5781SDZ evaluation board together with the Xilinx KC705 FPGA board, the Xilinx Embedded Development Kit (EDK) and the Micrium µC-Probe run-time monitoring tool. Below is presented a picture of the EVAL-AD5781SDZ Evaluation Board with the Xilinx KC705 board.
For component evaluation and performance purposes, as opposed to quick prototyping, the user is directed to use the part evaluation setup. This consists of:
- 1. A controller board like the SDP-B ( EVAL-SDP-CS1Z)
- 2. The component SDP compatible product evaluation board
- 3. Corresponding PC software ( shipped with the product evaluation board)
The SDP-B controller board is part of Analog Devices System Demonstration Platform (SDP). It provides a high speed USB 2.0 connection from the PC to the component evaluation board. The PC runs the evaluation software. Each evaluation board, which is an SDP compatible daughter board, includes the necessary installation file required for performance testing.
Note: it is expected that the analog performance on the two platforms may differ.
Below is presented a picture of SDP-B Controller Board with the EVAL-AD5781SDZ Evaluation Board.
The EVAL-AD5781SDZ is a full-featured evaluation board, designed to allow the user to easily evaluate all features of the AD5781 voltage output, 18-bit DAC. The AD5781 pins are accessible at on-board connectors for external connection. The board can be controlled by two means, via the on-board connector (J6) or via the system development platform connector (J3).
The AD5781 is a high precision, 18-bit digital-to-analog converter (DAC), designed to meet the requirements of precision control applications. The output range of the AD5781 is configured by two reference voltage inputs. The device is specified to operate with a dual power supply of up to 33 V.
More information
- AD5781 Product Info - pricing, samples, datasheet
Getting Started
The first objective is to ensure that you have all of the items needed and to install the software tools so that you are ready to create and run the evaluation project.
Required Hardware
- FMC-SDP adapter board
- EVAL-AD5781 evaluation board
Required Software
- Xilinx ISE 13.4 (Programmer (IMPACT) is sufficient for the demo and is available on Webpack).
- uC-Probe run-time monitoring tool
Downloads
The following table presents a short description the reference design archive contents.
| Folder | Description |
|---|---|
| Bit | Contains the KC705 configuration file that can be used to program the system for quick evaluation. |
| Microblaze | Contains the EDK project for the Microblaze softcore that will be implemented in the KC705 FPGA. |
| Software | Contains the source files of the software project that will be run by the Microblaze processor. |
| uCProbeInterface | Contains the uCProbe interface and the .elf symbols file used by uC-Probe to access data from the Microblaze memory. |
Run the Demonstration Project
Hardware Setup
Before connecting the ADI evaluation board to the Xilinx KC705 make sure that the VADJ_FPGA voltage of the KC705 is set to 3.3V. For more details on how to change the setting for VADJ_FPGA visit the Xilinx KC705 product page.
- Use the FMC-SDP interposer to connect the ADI evaluation board to the Xilinx KC705 board on the FMC LPC connector.
- Connect the JTAG and UART cables to the KC705 and power up the FPGA board.
- Start IMPACT, and double click “Boundary Scan”. Right click and select Initialize Chain. The program should recognize the Kintex 7 device (see screenshot below).
- Program the KC705 FPGA using the ”Bit/download.bit” file provided in the reference design archive.
- Power the ADI evaluation board.
At this point everything is set up and it is possible to start the evaluation of the ADI hardware through the controls in the uC-Probe application provided in the reference design.
Configure uC-Probe
Launch uC-Probe from the Start → All Programs → Micrium → uC-Probe.
Select uC-Probe options.
- Click on the uC-Probe icon on the top left portion of the screen.
- Click on the Options button to open the dialog box.
Set target board communication protocol as RS-232
- Click on the Communication tab icon on the top left portion of the dialog box
- Select the RS-232 option.
Setup RS-232 communication settings
- Select the RS-232 option from the Communication tab.
- Select the COM port to which the KC705 board is connected.
- Set the Baud Rate to 115200 bps.
- Press Apply and OK to exit the options menu.
Load and Run the Demonstration Project
- Click the Open option from the uC-Probe menu and select the .wsp file from the ucProbeInterface folder provided within the reference design files.
- Before opening the interface uC-Probe will ask for a symbols file that must be associated with the interface. Select the file ucProbeInterface/ADIEvalBoard.elf to be loaded as a symbol file.
- Run the demonstration project by pressing the Play button.
- In some cases it is possible that the uC-Probe interface will not respond to the commands the first time it is ran. In this situation just stop the interface by pressing the Stop button and run it again by pressing the Play button.
- After starting the uC-Probe interface wait until the status of the connection with the board displayed on the bottom of the screen is set to Connected. It is possible to use the interface only after the status is changed to Connected and the data transfer speed displayed next to the connection status is different than 0.
Demonstration Project User Interface
The following figure presents the uC-Probe interface that can be used for monitoring and controlling the operation of the EVAL-AD5781SDZ evaluation board.
The communication with the board is activated / deactivated by toggling the ON/OFF switch. The Activity LED turns green when the communication is active. If the ON/OFF switch is set to ON and the Activity LED is BLACK it means that there is a communication problem with the board. See the Troubleshooting section for indications on how to fix the communication problems.
The value of the AD5781 DAC Register is changed using the slider located under the DAC Register Value (18-bit) label. The selected value is displayed in the red numeric box located next to the slider.
The value of the AD5781 Clearcode Register is changed using the slider located under the Clearcode Register Value (18-bit) label. The selected value is displayed in the red numeric box located next to the slider.
The sliders Vref+ and Vref- are used to specify the reference voltages set on the evaluation board.
The DAC’s output voltage is displayed in the numeric box having the label Output voltage.
The values of the Control Register’s bits are indicated by the LEDs situated to the right of the Control Register label. When a LED id lit it means that the corresponding bit’s value is 1.
The values of the Status Control Register’s bits are indicated by the LEDs situated to the right of the Status Control Register label. When a LED id lit it means that the corresponding bit’s value is 1.
The DAC register coding is controlled by the DAC Register Coding switch. When the switch is set to the B0 position the binary offset coding is selected by setting the BIN/2sC bit of the Control Register to 1. When the switch is set to the C2 position the two’s complement coding is selected by setting the BIN/2sC bit of the Control Register to 0.
The Load DAC switch is used to control the LDAC signal of the AD5781. When the switch is pressed the DAC register (and consequently the DAC’s output) is updated with the contents of the DAC’s input register.
The RBUF Control switch is used to set the value of the RBUF bit from the Control Register. When the switch is active the bit’s value is set to 1.
Troubleshooting
In case there is a communication problem with the board the follwing actions can be perfomed in order to try to fix the issues:
- Check that the evaluation board is powered as instructed in the board's user guide.
- In uC-Probe refresh the symbols file by right-clicking on the System Browser window and selecting Refresh Symbols.
- If the communication problem persists even after performing the previous steps, restart the uC-Probe application and try to run the interface again.
More information
- Example questions:
- 2x FMCOMMS1 on 1x Kintex-7? by ndpr43
- ADFMCOMMS1-EBZ RF Bypass via RF switch by AdrianHolmes
- CVT-ADC-FMC-INTPZB FMC Adapter Board and AD9629 by davekirl
- FMCOMMS TX DAC sample size hangup by AnalogDiode