Verilog Code for Seven-Segment Display

 Verilog Code for Seven-Segment Display:

An Introduction to Seven-Segment Display and FPGA Implementation

In the world of digital electronics, seven-segment displays have become a common and widely used component for displaying numerical and alphanumeric information. With their simple design and ease of use, they have found applications in various areas, including digital clocks, calculators, digital meters, and more. In this blog post, we will explore the basics of seven-segment displays, their working principle, and how to interface them with an FPGA board using Verilog HDL.

Understanding Seven-Segment Display:

A seven-segment display is a form of electronic display device that consists of seven LED segments (A to G) arranged in a specific pattern to form numerical digits (0-9) and sometimes alphabets (A-F). Each segment can be individually controlled to turn on or off, allowing the formation of different characters. The eighth segment, called the dot segment (DP), is used for decimal point placement.

Working Principle:

To display a specific digit or character on a seven-segment display, you need to apply the corresponding combination of high and low signals to the segment inputs. By selectively turning on/off the segments, you can form the desired pattern. For example, to display the number "1," you would turn on segments B and C, while keeping the rest off.

FPGA Implementation:

Now, let's dive into how we can interface a seven-segment display with an FPGA board using Verilog HDL. We'll assume that we have a common cathode seven-segment display, where the common pin (cathode) is connected to the ground (GND). The FPGA board will provide the necessary control signals to turn on/off the segments.

Verilog Code:

First, let's define the connections between the FPGA pins and the seven-segment display segments. We'll assume that the display segments are connected to output pins on the FPGA board:

module SevenSegment( input wire [3:0] digit, output wire [6:0] segments );

// Segment mapping for common cathode display

assign segments = (digit == 4'b0000) ? 7'b1000000 :  // 0

                  (digit == 4'b0001) ? 7'b1111001 :  // 1

                  (digit == 4'b0010) ? 7'b0100100 :  // 2

                  (digit == 4'b0011) ? 7'b0110000 :  // 3

                  // Define mappings for the rest of the digits

endmodule

In the code above, we define a Verilog module called `SevenSegment` that takes a 4-bit input `digit` to select the digit to be displayed. The `segments` output is a 7-bit vector that controls the state of each segment (A to G). The mapping for each digit is defined using a conditional operator.

Instantiating the Module:

To use the `SevenSegment` module, you need to instantiate it in your top-level design module and connect the required inputs and outputs to the FPGA pins. Here's an example of how you can instantiate and use the `SevenSegment` module:

module TopLevelModule(// Define your other inputs and outputs here );

// Instantiate the SevenSegment module

SevenSegment sevenSeg(

  .digit(digitInput),

  .segments(segmentsOutput)

);

// Define the rest of your logic and connections

endmodule

In the code above, `digitInput` is the 4-bit input that selects the digit to be displayed, and `segmentsOutput` is the 7-bit vector that controls the segments of the seven-segment display.

Conclusion:

Seven-segment displays are versatile and widely used components in digital electronics. By understanding their working principle and how to interface them with an FPGA board using Verilog HDL, you can create various applications involving numerical and alphanumeric displays. Whether you're building a digital clock, a calculator, or any other project that requires visual representation of digits, the seven-segment display coupled with FPGA implementation provides an efficient and flexible solution.

By leveraging the power of FPGAs, you can easily control the segments of a seven-segment display, allowing you to create dynamic and interactive visual outputs. With the provided Verilog code, you can start experimenting with your own projects and explore the endless possibilities of this classic display technology.

Remember to check the documentation and pin assignments of your specific FPGA board to ensure proper connections and compatibility with the code. Happy coding!

Note: This blog post provides a high-level overview of seven-segment displays and FPGA implementation. For detailed implementation and specific FPGA board requirements, refer to the manufacturer's documentation and resources.

Show your results from Lab 2 on a seven segment display