This document presents the steps to setup an environment for using the EVAL-AD5791SDZ 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-AD5791SDZ 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:
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-AD5791SDZ Evaluation Board.
The AD5791 is a single 20-bit, unbuffered voltage-output DAC that operates from a bipolar supply of up to 33 V. The AD5791 accepts a positive reference input in the range 5 V to VDD - 2.5 V and a negative reference input in the range VSS + 2.5 V to 0 V. The AD5791 offers a relative accuracy specification of ±1 LSB max, and operation is guaranteed monotonic with a ±1 LSB DNL maximum specification.
The EVAL-AD5791 evaluation board is a full-featured evaluation board, designed to allow the user to easily evaluate all features of the AD5791 voltage output, 20-bit DAC. The AD5791 pins are accessible at on-board connectors for external connection.
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.
The following table presents a short description the reference design archive contents.
|Bit||Contains the KC705 configuration file that can be used to program the system for quick evaluation.|
|Microblaze||Contains the EDK 13.4 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 Microbalze memory.|
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.
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.
Launch uC-Probe from the Start → All Programs → Micrium → uC-Probe.
Select uC-Probe options.
Set target board communication protocol as RS-232
Setup RS-232 communication settings
The following figure presents the uC-Probe interface that can be used for monitoring and controlling the operation of the EVAL-AD5791SDZ 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 AD5791 DAC Register is changed using the slider located under the DAC Register Value (20-bit) label. The selected value is displayed in the numeric box located next to the slider.
The value of the AD5791 Clearcode Register is changed using the slider located under the Clearcode Register Value (20-bit) label. The selected value is displayed in the 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 is lit it means that the corresponding bit 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 is lit it means that the corresponding bit 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 AD5791. 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.
In case there is a communication problem with the board the follwing actions can be perfomed in order to try to fix the issues: