FPGA Introductory Tutorial: Part 1

Transcription

1 FPGA Introductory Tutorial: Part 1 This tutorial is designed to assist in learning the basics of the Altera Quartus II v9.0 software. Part 1 of the tutorial will cover the basics of creating a Project, building a circuit using a Block Diagram, and then conducting a Functional Simulation to verify that the circuit is functioning as intended. Finally, the tutorial will cover how to program your FPGA board. Project Setup and Block Diagram: 1) Start the Quartus II software. By default, a shortcut to the program is located in the Engineering Applications folder within the Start menu of the lab computers. 2) Once the program loads, start a new project by going to File New Project Wizard An introductory screen will load describing the wizard. Click the Next button to start the wizard. 3) A screen similar to the one below will load. The working directory is where the files for your project are saved. You may save the files wherever you chose, but it is highly recommended you save your project in CEFNS student file server named Kashyyyk. This will enable you to access your project from any computer in the lab. By default, your Kashyyyk drive is your I: drive. The name of the project and the name of the toplevel design entity may be named whatever you choose. However, make note of the toplevel design entity name, as you will need it later. 1-1

2 4) Click the Next button. This screen will allow you to add files to your project. For this tutorial, we will not need to add any further files, so click Next button to move on to the next screen. 5) The next part of the tutorial will ask you to enter the type of FPGA chip that you plan on programming. Since we are programming a Cyclone II board, select Cyclone II as the device family. Then scroll down the Available devices list and select the appropriate chip. The chip name is physically printed on the Cyclone II chip located on your FPGA board. Note: The chip selected below may not match your chip; ensure you select the correct chip name. 6) After you select the correct chip, click Finish to end the wizard. 1-2

3 7) Next, create a new Block Diagram file. To do this, click New under the File menu. Select Block Diagram/Schematic File and click OK. 8) Now we will add our first logic element to our schematic. Click on the Symbol Tool located on the toolbar on the left (it looks like a miniature AND gate). 1-3

4 9) A window will appear asking you to select the symbol. For this tutorial we will use a 2- input AND gate. Expand the primitives folder, followed by the logic folder and select the 2-input AND gate (called and2 ). Click OK. 10) Your cursor will now appear with the 2-input AND gate attached. Click anywhere on your schematic to place the AND gate. 11) Next, return to the Symbol Tool. This time, select an input pin (located within the primitives pin folder). Place two input pins on your schematic. Repeat the same step to place one output pin on your schematic. When done, your schematic should look similar to the one below: 1-4

5 12) Now connect your input pins to the two inputs on the AND gate, and the output pin to the output on the AND gate. This can be done by moving the cursor close a connection point until the cursor changes into a square target. Then click and drag your cursor to the matching connection point. Once finished, your schematic should look similar to the one below: 13) Next, the pin names need to be changed to their appropriate name. This can be done by right clicking on the pin, and editing the properties. Name your input pins A and B, and your output pin Y. 1-5

6 14) Your Block Diagram is finished! Save your file in your working directory. MAKE SURE YOUR FILE NAME IS THE SAME NAME AS YOUR TOP-LEVEL DESIGN ENTITY NAME. You specified this name during the project creation wizard. If the names are different, the simulation and programming will not work. Functional Simulation: 1) Now that your schematic is created, we need to compile your circuit in order to prepare it for simulation. This can be done by pressing the purple play icon in the top toolbar. If your circuit won t compile because of errors, go back to your Block Diagram and fix your errors. If you need any help, ask your TA or instructor. 2) The next step is to create the input waveform plots used by the simulator. Create a new Vector Waveform by going to File New and select Vector Waveform File. 1-6

7 3) Now we need to add the pins to the plot. This can be done by double clicking in the white space under the Name and Value at title. Then select the Node Finder button. 4) Type * in the Named box. Change the Filter to Pins: unassigned. Then click the List button to list all of the available nodes. Select A, B, and Y and move them to the Selected Nodes list. Then click OK. 1-7

8 5) Once all three pins are on the waveform plot, we need to set the values of the input pins for a successful simulation. To verify that the AND gate is working correctly, the simulation must cycle through all possible combination of inputs. Below is a list of all possible input combinations for a 2-input AND gate: Combination 1: A = 0, B = 0 Combination 2: A = 0, B = 1 Combination 3: A = 1, B = 0 Combination 4: A = 1, B = 1 Now we must input these combinations into the waveform plot. The value of a wave may be changed by dragging a box around the part of the wave to be edited. Once the wave is selected, clicking Forcing High or Forcing Low on the left toolbar will change the value to either a logical 1 or a logical 0. In the example below, A was selected between 10.0 ns and 20.0 ns and changed to a logical

9 6) Continue editing the waveform plot until all four possible combinations are placed in the plot. Below is a waveform plot demonstrating a completed plot with all four possible combinations. 7) Once your plot is finished, save the file with an appropriate name of your choice in your working directory. 8) Now it is time to simulate your circuit. Start the simulator by going to Processing Simulator Tool. Change the Simulation mode to Functional. Place your newly created Vector Waveform file in the Simulation Input box. Clicking the button will allow you to browse to the correct file. 1-9

10 9) Now press the Generate Functional Simulation Netlist button. In successful, a box should appear confirming that the netlist generation was successful. 10) Now click the Start button to begin the simulation. Once the simulation is completed click the Report button to see the simulation results. Notice how the output, Y, only goes high when both inputs are high. The AND gate circuit is working correctly! 1-10

11 Programming the FPGA Board: 1) Before the FPGA board is programmed, the pins in the Block Diagram file must be matched up with the correct physical pins on the FPGA board. Pins may be assigned using the Pin Planner tool. To start the tool, select Pins under the Assignments menu. A window will appear showing a layout of your Cyclone II chip and all available pins. 2) Using the pin list located on Vista, find the appropriate pin numbers for your inputs and outputs. For our 2-input AND gate, we will attach the inputs to two of the toggle switches (SW[0] and SW[1]), and the output to one of the green LEDs (LEDG[0]). Below is a summary of the pins and their assignments on the physical board: Input A: SW[0] - PIN_L22 Input B: SW[1] - PIN_L21 Output Y: LEDG[0] - PIN_U

12 3) Once you have selected the correct pins, input the pin numbers in the Location column, as seen below: Close the Pin Planner. If your pins are inputted correctly, the pin number should appear next to the inputs and outputs in your block diagram file: 4) Next, recompile your project by pressing the purple play button in the top toolbar. Fix any errors, if necessary. 5) Finally, we will program the FPGA board using the Programmer tool, located under the Tools drop down menu. Be sure to plug in your FPGA board, if you haven t already done so. 6) Once the Programmer window pops up, click the Hardware Setup button located in the top left corner. 1-12

13 7) Change Currently selected hardware to USB-Blaster, and click Close. 8) Once you have selected the correct hardware, hit the Start button to program the device. The board is now programmed with your circuit! 1-13