A good helper for general prototyping and testing - Artix-7 50T entry-level FPGA evaluation kit hands-on review

FPGA , or field programmable gate array, is a type of programmable logic device. With the advancement of technology and the continuous development of EDA design tools, the threshold of FPGA (learning cost and price cost) is getting lower and lower, and it has become one of the mainstream platforms for realizing digital systems. The integration of FPGA is getting higher and higher, while the corresponding power consumption and cost are constantly decreasing, making it widely used in various fields. Like the butterfly effect, more application fields have also prompted various FPGA manufacturers to make more and more detailed divisions of their products. For products, this is a good thing, but for hardware engineers, the benefit is that they can save costs by selecting on demand, but it also means that device selection and resource evaluation need to be more cautious.

When engineers are choosing an FPGA development board, the first question they ask is what can we get and what are we going to use it for? For beginners, FPGAs are still quite daunting, but if you have a good evaluation board as a start, you will be able to achieve twice the result with half the effort. Perhaps getting started with FPGAs is not as difficult as the legend says. Today, AVNET will introduce you to a general-purpose, low-cost FPGA development kit - the Artix-7 50T FPGA evaluation kit launched by AVNET.

Artix-7 devices achieve low cost and low power consumption in the 28nm process, and are optimized to achieve the best combination of performance and power consumption in the design. In addition, Artix-7 devices have very significant features, integrating AMS, transceiver and other functions, and can be widely used in software-defined radio, machine vision photography and low-end wireless backhaul fields.

Next, let's take a look at the Artix-7 50T evaluation kit. In addition to the evaluation board, the box also comes with a network cable and two MicroUSB cables. Some people may wonder why there are two MicroUSB cables? In fact, one is used for serial port output and power supply ( if there is no corresponding adapter, you can also consider directly powering through the USB interface on the computer, which can provide about 500mA current, which can basically meet most of the application requirements of the board. If the board connector is connected to too many peripherals, you can also use the power socket (J13) for external DC power supply. ) , and the other is used for downloading and debugging the board , and does not provide power supply .

The board is a dark red PCB board, which is not too big, about the size of an adult's palm, and has solid workmanship. The manual and other information of the Artix-7 50T FPGA evaluation kit can be downloaded for free from the AVNET official website. It is worth mentioning that AVNET provides a full set of circuit diagrams for the board, which is a very good reference for those who want to understand and start the circuit design of the Artix-7 series FPGA chip.

It is worth mentioning that the Artix-7 50T FPGA evaluation kit provides 6 Pmod connectors, each of which includes 2 power signals, 2 low signals and 8 I/O signals. Pmod connectors are mainly used to connect some low-speed and low-pin external modules. It should be noted that the signal routing from the PCB board to the Pmod connector does not consider the impedance and signal matching issues. There are various Pmod peripheral modules on the market, and designers can flexibly choose according to their needs, which greatly improves the expansion performance.

Let’s focus on the main FPGA chip on the board , the specific model is XC7A50T-1FTG256C.

XC7A50T-1FTG256C is an intermediate configuration model in the Artix-7 series FPGA, which includes 52160 logic units, 120 DSP slices, 2700Kb memory, 4 GTP transceivers, etc. For detailed configuration parameters, please refer to the table below.

The Artix-7 50T FPGA evaluation kit is very simple and convenient to use. Two micro-USB cables can handle everything. One is used for power supply, and no additional voltage regulator or transformer is required, which is really good news for engineers; the other is used for downloading and debugging, and no additional emulator is required, which is convenient for engineers to develop.

After the board is powered on through the MicroUSB interface, you will be prompted to install the onboard USB-to-serial port chip driver. This chip is the CP210X series from Silicon Labs, which is very common. Many engineers may have the driver for this chip on their computers. Otherwise, we can also find the driver online. After installation, you can see the corresponding serial port. The serial port function of the board is required to use the built-in demonstration program of the board.

Set the baud rate to 115200, 8 bits, no parity, 1 stop bit, and reset the board to see the serial port output.

The built-in program of the board is to verify the various functions of the board, including I2C, DDR3, LED, Switch, and button. The author tried them one by one and found no problem in the implementation of these five functions.

The built-in routines of the board can help users become familiar with the board functions as quickly as possible, which is very meaningful.

The Artix-7 50T FPGA evaluation kit can use Xilinx's official EDA design tool Vivado, which is a very powerful tool. Unfortunately, to use all its functions, you need Lince, and the complete installation package is also unusually large, with a capacity of more than 11GB, which is a bit scary. The official website has also launched a web installation package, which is very convenient. You can select the devices you need in the most concise way. You can download the installation program from the official website.

However, for users with poor network connection, it is not recommended to use the web installation board. It is easy to get stuck halfway through the installation and you may have to start over from the beginning. This is indeed a bit of a loss. Perhaps directly downloading the offline installation package is suitable for you.

For users who are new to the VIVADO tool, they may encounter many problems, such as software configuration and the use of basic functions. Fortunately, the Artix-7 50T FPGA evaluation kit provides a "step-by-step" tutorial guidance. Users can follow the steps step by step. First, install the definition file 7A50T_Board_Definition_Files_Vivado of the Artix-7 50T FPGA evaluation board in the VIVADO tool (the file is provided on the AVNET official website), and copy the contents of this folder to the artix7 folder directory of the Vivado software.

After the installation is complete, we can use it to generate a design project based on the MicroBlaze soft-core processor and create a new project from the VIVADO design tool.

Under Boards we can find the Artix-7 50T FPGA evaluation kit.

Follow the instructions in the User Guide (User Guide) provided on the official website. The process is very detailed and will not be described in this article.

One thing worth noting is that when the design is completed and you want to download the compiled file through the onboard emulator, you will use the COM port of another MicroUSB interface, which is different from the USB to serial port method and needs to be treated differently. The COM port driver will prompt you to install it when installing the VIVADO tool.

In addition, the Artix-7 50T FPGA evaluation kit also includes other related demo resources, such as LwIP, Proximity_Sensor and other applications. Due to the length of this article, many functions of the board cannot be displayed one by one. Engineers who are interested in this aspect can click "View original text" to view it.

It must be mentioned that the Artix-7 50T FPGA evaluation board is a very complete system development tool kit, and it is also a good helper for general prototyping and testing. It integrates all the functions and interfaces required for embedded processor systems into the XC7A50T-1FTG256C chip, which is suitable for embedded engineers who are interested in MicroBlaze soft processors or Artix-7 FPGAs and have requirements for low-power platforms. Whether it is evaluating industrial Ethernet protocols, integrating multiple sensors, or running Linux-based Web servers, the Artix-7 50T FPGA evaluation board can help engineers verify new design concepts.