Fpga Based System

tutorial 2 excogitation to apply the PicoBlaze Microcontroller 1 The Spartan-3E tutorial 2 gateway to using the PicoBlaze Microcontroller sport 1. 0 Author Jasmine Banks 2012, Queensland University of Techno lumberarithmy Xilinx Spartan-3E as undisputable sailing master adjustment 14. 3 tutorial 2 accession to using the PicoBlaze Microcontroller 2 Xilinx Spartan-3E image sailing master interpretation 14. 3 tutorial 2 installation to utilize the PicoBlaze Microcontroller 3 Acknowledgements Parts of this tutorial ar based on an earlier version indite for protrusion sailing master version 9. , written by Michael Bakker, Matthew Grace and Warwick Kilroy, as part of ENB345 Advanced give the axe in 2008. Xilinx Spartan-3E stand out navigator Version 14. 3 Tutorial 2 inception to apply the PicoBlaze Microcontroller 4 Xilinx Spartan-3E advise navigator Version 14. 3 Tutorial 2 Introduction to using the PicoBlaze Microcontroller 5 Glossary ALU state of matter FPGA JTAG guide KCPSM3 Arithmetic Logic Unit Disk roll System Field Programmable Gate Array joint Test Action Group Light Emitting Diode (K)Constant Coded Programmable State Machine a very b be(a) 8-bit microcontroller optimised for Spartan-3 devices 2.Reduced Instruction Set Computing VHSIC Hardware Description Language Very High Speed unified Circuit RISC VHDL VHSIC Xilinx Spartan-3E come out sailing master Version 14. 3 Tutorial 2 Introduction to development the PicoBlaze Microcontroller 6 Xilinx Spartan-3E render navigator Version 14. 3 Tutorial 2 Introduction to victimisation the PicoBlaze Microcontroller 7 circuit board of Contents page Acknowledgements . Glossary . . List of figures . . . List of Tables 1. 0 Introduction . . 1. 1 Design Functionality .. .. 1. 2 Relevant Documentation .. . .. . 1. 3 Pre-requisite Knowledge .. 1. 4 Scope . .. 2. 0 Equipment . 3. 0 ground The PicoBlaze Microcontroller .. 4. 0 Procedure Part 1 PicoBlaze .. . 4. 1 PicoBlaze Down load .. 4. 2 Copy Files . 4. 3 multitude Language Code . 4. barragenel the Assembler .. 5. 0 Procedure Part 2 Project navigator .. 5. 1 get goingup . 5. 2 Creating a recent Project . . . 5. 3 Adding ascendant Files .. 5. 4 tutorial. vhd and kcpsm3. vhd Observations . . . 5. 5 Adding a top_ take Entity .. 5. 6 Editing the top_level Entity . 5. 7 top_level. vhd Code . . 5. 8 syntax Checking 5. 9 Pin appointment .. 5. 10 Synthesize, Translate, Map and ready & Route .. .. . 5. 11 Download Design to poster .. 6. 0 Running the Program on the Spartan-3E Board .. 7. 0 Further Information 8. 0 savoir-faires . Appendix A top_level. vhd 3 5 9 13 15 15 15 15 15 17 19 21 21 21 22 23 31 31 32 35 38 40 45 49 52 54 59 61 75 77 79 81 Xilinx Spartan-3E Project navigator Version 14. 3Tutorial 2 Introduction to victimization the PicoBlaze Microcontroller 8 Xilinx Spartan-3E Project sailing master Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcon troller 9 List of mannikins page public figure 2. 1 Spartan-3E Development Board construe 3. 1 PicoBlaze partings .. . examine 3. 2 KCPSM3 comp anent declaration . type 3. 3 bar warehousing component declaration . . understand 4. 1 KCPSM3 accommodates subsequently unzipping participate 4. 2 Simple PicoBlaze curriculum . . . bod 4. 3 Files in the examning(a) directory .. record 4. 4 KCPSM3 assembler turn ons .. . realise 4. 5 res publica influence straightaway windowpane, later on changing to working(a) directory count 4. 6 DOS Command Prompt window, with KCPSM3 command typed in .. go into 4. 7 DOS Command Prompt window, after KCPSM3 successfully run . record 4. 8 Error message which advances if KCPSM3 is run on a 64-bit tool bit 4. 9 DOSBox window see to it 4. 10 DOSBox window, with KCPSM3 command typed in .. .. Figure 4. 11 DOSBox window, after KCPSM3 successfully run . Figure 4. 12 Files in the working directory after KCPSM3 successfully run . Figure 5. 1 Project navigator Software Startup Window . Figure 5. 2 in the buff Project Wizard, create New Project Page . .Figure 5. 3 New Project Wizard, Project Settings Page . Figure 5. 4 New Project Wizard, Project compend Page Figure 5. 5 Adding a cite file to the project .. . Figure 5. 6 Add consultation file selection window .. Figure 5. 7 Adding base Files window Figure 5. 8 kcpsm3 and tutorial in the Sources window . 7 19 20 20 21 22 22 23 23 24 24 25 26 27 28 29 31 32 33 34 35 36 36 37 Xilinx Spartan-3E Project sailing master Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 10 Figure 5. 9 Source mark for tutorial. vhd uncovered in a tab . Figure 5. 10 tutorial entity .. Figure 5. 11 kcpsm3 entity . .. . Figure 5. 12 Adding a source file to the project .. Figure 5. 3 New Source Wizard, Select Source Type . Figure 5. 14 New Source Wizard, make Module . Figure 5. 15 New Source Wizard, Summary . . .. Figure 5. 16 top_level in the Sources window .. Figure 5. 17 top_level. vhd, as displayed in Project Navigator, before editing .. Figure 5. 18(a) computer architecture of top_level. vhd, part 1 .. .. Figure 5. 18(b) Architecture of top_level. vhd, part 2 . .. Figure 5. 19 top_level in the Sources window ..Figure 5. 20 Component declarations . Figure 5. 21 Signal declarations Figure 5. 22 Component instantiations .. Figure 5. 23 Input ports .. Figure 5. 24 Output ports .. Figure 5. 5 dowry of Project Navigator secrecy with Synthesize XST expanded .. .. Figure 5. 26 A green tick next to Check Syntax shows that no errors were found . Figure 5. 27 Example where an error was purposely introduced Figure 5. 28 Portion of Project Navigator screen, with User Constraints expanded . Figure 5. 29 Dialog Box asking if you invite to create an toolation Constraint File . . Figure 5. 30 Initial appearance of PlanAhead window . Figure 5. 31 I/O Ports displayed in a separate window . 38 38 39 40 41 42 43 44 45 46 47 48 49 50 50 51 51 52 53 53 55 55 56 56Xilinx Spartan-3E Project Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 11 Figure 5. 32 I/O Ports window with individual ports expanded . . Figure 5. 33 I/O Ports window with values filled in . Figure 5. 34 Portion of Project Navigator screen, with apply Design expanded .. Figure 5. 35 Portion of Project Navigator screen, after Translate, Map and Place & Route have successfully been run . .. Figure 5. 36 Portion of Project Navigator screen, with Implement Design expanded .. Figure 5. 7 Portion of Project Navigator screen, after Generate programme File has successfully been run . . Figure 5. 38 The initial iMPACT window .. .. Figure 5. 39 iMPACT window, after double-clicking on Boundary Scan . Figure 5. 40 iMPACT window, viewing arrange Chain selected Figure 5. 41 iMPACT window, assign configuration files .. .. Figure 5. 42 iMPACT window, appointment the configuration file for the xc3e500e . .. Figure 5 . 43 iMPACT window, dialog misfortune asking if we wish to stick to an SPI or BPI PROM . Figure 5. 4 iMPACT window, bypassing the xcf04s . Figure 5. 45 iMPACT window, bypassing the xc2c64a . .. Figure 5. 46 iMPACT window, Device Programming Proper get outs dialog box Figure 5. 47 iMPACT window, masking the device chain .. .. Figure 5. 48 iMPACT window, options which appear when right clicking on the xc3s500e .. Figure 5. 49 iMPACT window, after the program has been successfully downloaded to the Spartan-3E board .. Figure 6. 1 The Spartan-3E board with the program run . .. 57 58 59 60 61 2 63 64 65 66 67 68 69 70 71 72 72 73 75 Xilinx Spartan-3E Project Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 12 Xilinx Spartan-3E Project Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 13 List of Tables Page Table 5. 1 Input/ return ports of the top_level entity . .. Table 5. 2 Values to enter in the I/O Ports window . . 54 57 Xilinx Spartan-3E Project Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 14 Xilinx Spartan-3E Project Navigator Version 14. 3Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 15 1. 0 Introduction This tutorial is initiationed to sustain new users become familiar with using the PicoBlaze microcontroller with the Spartan-3E board. The tutorial gives a brief introduction to the PicoBlaze microcontroller, and hence steps through the following Writing a small PicoBlaze fabrication language (. psm) file, and stepping through the process of assembling the . psm file using KCPSM3. Writing a top level VHDL mental faculty to connect the PicoBlaze microcontroller (KCPSM3 component) and the program ROM, and to connect the required input and output ports.Connecting the top level module inputs and outputs to the switches, buttons and LEDs on the Spartan-3E board. Downloading the program to the Spartan-3E boar d using the Project Navigator software program. 1. 1 Design Functionality The compute written in this tutorial reads the values of the four switches and the four push buttons, and displays the current values on the octonary LEDS. 1. 2 Relevant Documentation Before commencing this tutorial, it would be helpful to download the Spartan-3E FPGA Starter Kit Board User Guide 1, and the PicoBlaze 8-bit Embedded Microcontroller User Guide 2. 1. Pre-requisite Knowledge Before commencing this tutorial, the user should work through The Spartan-3E Tutorial 1 Introduction to FGPA Programming 3. 1. 4 Scope This tutorial is designed to help the user who is just starting to get into using the PicoBlaze with the Spartan-3E. It steps through the process of creating a very unsophisticated PicoBlaze program, running the assembler, putting the VHDL components together in Project Navigator, and downloading the final program to the board. It is not designed to be a tutorial on VHDL syntax or to provid e detailed information on the PicoBlaze.For help with VHDL, the user can consult with a number of textbooks on the subject, such as 4,5, or envision help online. The book by Chu 6 is also a useful signifyence for the Spartan-3 with many useful examples. Reference designs for the Spartan-3E can also be found here 7. For detailed information about the features and education mark of the PicoBlaze, the user can consult the documentation in 2,8. Xilinx Spartan-3E Project Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 16 Xilinx Spartan-3E Project Navigator Version 14. 3Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 17 2. 0 Equipment The following are required to work through this tutorial The Xilinx ISE Project Navigator software. Version 14. 3 was used in this tutorial, but older versions of the software can be used. The software can be downloaded with a free WebPack license from the Xilinx website, http//www. xilinx. com/. The user leave behind need to immortalise and log in. The Spartan-3E Starter Kit, including the Spartan-3E development board, power cable and USB cable for PC connection. The Spartan-3E development board is shown in Figure 2. 1.The Picoblaze 8-bit Microcontroller software. The software can be downloaded for free from the Xilinx website, http//www. xilinx. com/. Again the user go out need to register and log in. If a 64-bit machine is being used, software which can run 32-bit DOS programs, such as DOSBox, lead be needed to run the KCPSM3 workable. DOSBox can be downloaded from http//www. dosbox. com/. Power JTAG ON/OFF Re make up ones mind thrust FPGA USB LCD LEDs Push Buttons Figure 2. 1 Spartan-3E Development Board. SW0-3 Xilinx Spartan-3E Project Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 18 . 0 Background The PicoBlaze Micocontroller The PicoBlaze is an 8-bit RISC microcontroller which is specifically designed and optimized for th e Spartan-3 family. iodine of its main advantages is its small size, requiring only 96 FPGA slices. It is provided as a free, source-level VHDL file with royalty-free re-use within Xilinx FPGAs 2. Figure 3. 1 shows that the PicoBlaze consists of two components. The KCPSM3 component provides the ALU, registers, scratchpad RAM etc. The Block Memory (Program) component stores the pedagogicss to be executed. This typically consists of a Block RAM, of 1024 bytes in size.Figure 3. 1 PicoBlaze components 8. The basic design process using the PicoBlaze follows the steps on a lower floor 1. A PicoBlaze program is written in assembly language. This file is given the extension . psm. 2. The KCPSM3 assembler is run on the . psm file, and a VHDL file (extension . vhd) which embeds the instructions in the Block Memory component, is output. The shout out of the . vhd file pass on be derived from the touch on of the . psm file, i. e. , if the . psm file is myprog. psm, then the . vhd file de parting be myprog. vhd. 3. The VHDL code for the Block Memory and KCPSM3 modules is loaded into Project Navigator.Further VHDL code will need to be written to connect the two modules and user interface to the outside world. 4. The project is compiled using the Project Navigator Software, and ultimately downloaded to the Spartan-3E board (or other target hardware). Figures 3. 2 and 3. 3 show the VHDL component declarations for the KCPSM3 and Block Memory respectively. Note that the name of the Block Memory component is derived from the name of the original . psm file, i. e. , if the . psm file was myprog. psm, the Block Memory component will be called myprog. Xilinx Spartan-3E Project Navigator Version 14. Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 19 component kcpsm3 port (address instruction port_id write_strobe out_port read_strobe in_port come apart interrupt_ack reset clk end component out std_logic_vector(9 downto 0) in std_logic_vector(17 down to 0) out std_logic_vector(7 downto 0) out std_logic out std_logic_vector(7 downto 0) out std_logic in std_logic_vector(7 downto 0) in std_logic out std_logic in std_logic in std_logic) Figure 3. 2 KCPSM3 component declaration. Name of component derived from name of . psm file omponent myprog port (address in std_logic_vector(9 downto 0) instruction out std_logic_vector(17 downto 0) clk in std_logic) end component Figure 3. 3 Block Memory component declarations. In addition, it is possible to download a new program into the Block Memory, using the JTAG port on the Spartan-3E board. This can provide a convenient means to update the program without having to recompile the VHDL code in Project Navigator. This is not covered by this introductory tutorial, and the user can refer to documentation such as 3 for more information. Xilinx Spartan-3EProject Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 20 4. 0 Procedure Part 1 PicoBlaze 4. 1 PicoBla ze Download 1. Download the file KCPSM3. zip from http//www. xilinx. com/. The version of the software for the Spartan-3 family should be chosen. 2. Unzip the file. After unzipping, the files should appear as shown in Figure 4. 1. Figure 4. 1 KCPSM3 files after unzipping. The file KCPSM3_Manual. pdf is listed as reference 8 in this tutorial. 4. 2 Copy Files 1. Create a directory called tutorial_2 in an appropriate location.This will be the working directory for the rest of this tutorial. 2. Copy the following files in the Assembler directory into tutorial_2 KCPSM3. EXE ROM_form. coe ROM_form. v ROM_form. vhd 3. Copy the following file in the VHDL directory into tutorial_2 kcpsm3. vhd Xilinx Spartan-3E Project Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 21 4. 3 Assembly Language Code 1. cleared a text editor (for example, Notepad or Wordpad), and enter the text shown in Figure 4. 2. The text consists of a very simple program written in the KCPSM3 assembly language.The program runs in an infinite loop, rendering the contents of an input port at address 00h (connected to the switches) into a register, and writing the contents of this register to an output port at address 80h (connected to the LEDs). Characters which appear after a in each line are comments. Simple loop that puts contents of input register into the output register switches DSIN $00 LEDS DSOUT $80 read switches into register s0 write contents of s0 to output port 80 leds. loop back to start start arousal s0, 00 OUTPUT s0, 80 JUMP start Figure 4. 2 Simple PicoBlaze program. . restrain your file to tutorial. psm, in the tutorial_2 directory. If using Notepad, be careful not to save the file as tutorial. psm. txt. The name of the file should be restricted to 8 characters. The tutorial_2 directory should now accept the files shown in Figure 4. 3. Figure 4. 3 Files in the tutorial_2 working directory. Xilinx Spartan-3E Project Navigator Vers ion 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 22 4. 4 Running the Assembler As shown in Figure 4. 4, the assembler takes the . psm file as input, as come up as three Block RAM initialisation templates.Fifteen different output files are produced. In this tutorial, we will be using the . vhd output file. Figure 4. 4 KCPSM3 assembler files 2. The assembler is a DOS executable file, KCPSM3. exe, which can be run in a DOS Command Prompt window. 4. 4. 1 32-bit Operating Systems 1. Open a DOS Command Prompt window by selecting StartAll ProgramsAccessoriesCommand Prompt 2. Use the cd command to channel into the tutorial_2 working directory, as shown in Figure 4. 5. Figure 4. 5 DOS Command Prompt window, after changing to working directory. Xilinx Spartan-3E Project Navigator Version 14. 3Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 23 3. Now type the command KCPSM3 tutorial. psm, as shown in Figure 4. 6. Figure 4. 6 DOS Command Prompt window , with KCPSM3 command typed in. After entering the command KCPSM3 tutorial. psm, numerous messages should fly past on the screen, ending with KCPSM3 successful. KCPSM3 jazz, as shown in Figure 4. 7. After the assembler has successfully run, the working directory should contain many more files, as shown in Figure 4. 12. Figure 4. 7 DOS Command Prompt window, after KCPSM3 successfully run. 4. Type exit to close the Command Prompt window.Xilinx Spartan-3E Project Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 24 4. 4. 2 64-bit Operating Systems The KCPSM3 executable will only work on 32-bit operating systems. If you are using a 64-bit machine and attempt to run KCPMS3 in a DOS Command Prompt window, the error message shown in Figure 4. 8 will appear. Figure 4. 8 Error message which appears if it is attempted to run KCPSM3 on a 64-bit machine. hotshot way to work around this and run KCPSM3 is to use the DOSbox software, which can be downloaded f rom http//www. dosbox. com/. 1.Download and run DOSBox. 2. Mount the working directory and change into this directory. When DOSbox is started up, a command window which resembles the DOS Command Prompt window appears. However, it is first necessity to mount the working directory to a drive letter before being able to enter this directory and run programs. This is done with the mount command mount Figure 4. 9 shows the commands entered to mount and change into the working directory. In this case, the working directory is mounted as drive letter c. The command c is then used to change into this directory. Xilinx Spartan-3EProject Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 25 Figure 4. 9 DOSBox window, commands entered to mount and change into the working directory. 3. Now type the command KCPSM3 tutorial. psm, as shown in Figure 4. 10. Xilinx Spartan-3E Project Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcont roller 26 Figure 4. 10 DOSBox window, with KCPSM3 command typed in. After entering the command KCPSM3 tutorial. psm, numerous messages should fly past on the screen, ending with KCPSM3 successful. KCPSM3 complete, as shown in Figure 4. 11.After the assembler has successfully run, the working directory should contain many more files, as shown in Figure 4. 12. Xilinx Spartan-3E Project Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 27 Figure 4. 11 DOSBox window, after KCPSM3 successfully run. 4. Type exit to close DOSBox. Xilinx Spartan-3E Project Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 28 Figure 4. 12 Files in the working directory after KCPSM3 successfully run. Xilinx Spartan-3E Project Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 9 Xilinx Spartan-3E Project Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 30 5. 0 Proc edure Part 2 Project Navigator 5. 1 Startup Start the Project Navigator software by selecting StartAll ProgramsXILINX Design ToolsXilinx ISE Design Suite 14. 3ISE Design Tools32 bit Project Navigator or StartAll ProgramsXILINX Design ToolsXilinx ISE Design Suite 14. 3ISE Design Tools64 bit Project Navigator depending on your system. The Xilinx Project Navigator software should start. The initial window which appears on startup should appear as shown in Figure 5. . Figure 5. 1 Project Navigator Software Startup Window. Xilinx Spartan-3E Project Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 31 5. 2 Creating a New Project 1. Select FileNew Project. The New Project Wizard will appear. 2. Type tutorial_2 in the Name field. 3. Choose mend and Working Directory as the tutorial_2 working directory. 4. Verify that Top-level source type is selected as HDL. 5. The properties should now be set as shown in Figure 5. 2. finish off Next to mov e to the Project Settings page. Figure 5. 2 New Project Wizard, Create New Project Page. 6.Fill in the properties as follows Evaluation Development Board no(prenominal) Specified or Spartan-3E Starter Board harvest-tide Category All Family Spartan3E Device XC3S500E Xilinx Spartan-3E Project Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 32 Package FG320 Speed site -4 Top-Level Source Type HDL Synthesis Tool XST (VHDL/Verilog) Simulator ISim (VHDL/Verilog) Preferred Language VHDL Property Specification in Project File Store All Values Manual Compile Order unchecked VHDL Source Analysis Standard VHDL-93 Enable Message Filtering uncheckedNote if you choose Evaluation Development Board as Spartan-3E Started Board, properties from Product Category through to Speed will be filled in mechanically. However, you must make sure that Preferred Language is set to VHDL. The properties should now be filled in as shown in Figure 5. 3. Figure 5. 3 New Project Wizard, Project Settings Page. Xilinx Spartan-3E Project Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 33 7. Click Next to move to the Project Summary page, which will appear as shown in Figure 5. 4. Figure 5. 4 New Project Wizard, Project Summary Page. 8.Click Finish to exit the New Project Wizard. Xilinx Spartan-3E Project Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 34 5. 3 Adding Source Files 1. Select ProjectAdd Source as shown in Figure 5. 5. A window will appear allowing you to choose one or more files. Figure 5. 5 Adding a source file to the project. 2. Select TUTORIAL. VHD and kcpsm3. vhd as shown in Figure 5. 6. Both files can be selected at once by clicking on the first filename, holding down the CTRL key and clicking the second filename. Alternatively, one file can be selected and steps 1-3 repeated for the second file.Xilinx Spartan-3E Project Navigator Version 14. 3 Tu torial 2 Introduction to Using the PicoBlaze Microcontroller 35 Figure 5. 6 Add Source file selection window. 3. The Adding Source Files window will now appear as shown in Figure 5. 7, showing the two files selected to be added to the project. Click OK. Figure 5. 7 Adding Source Files window. Xilinx Spartan-3E Project Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 36 As shown in Figure 5. 8, kcpsm3 and tutorial will now appear in the Sources window. Doubleclicking on either filename in the Sources window will display the file in a tab.Sources Window Figure 5. 8 kcpsm3 and tutorial in the Sources window. Xilinx Spartan-3E Project Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 37 5. 4 tutorial. vhd and kcpsm3. vhd Observations 1. Double-click on tutorial in the Sources window. This will display the source code in a tab, as shown in Figure 5. 9. It can be seen that Project Navigator glossiness codes the t ext of VDHL files, to make them easier to read. Comment lines, which start with - - are displayed in green. Reserved words of the VHDL language are displayed in blue, while VHDL types are displayed in red.Everything else is remaining as black. tutorial in Sources window Source code for tutorial. vhd appears in this tab Figure 5. 9 Source code for tutorial. vhd is displayed in a tab. A close up of the code for the tutorial entity is shown in Figure 4. 10. Note that this corresponds to the Block Memory (Program) component of Figures 3. 1 and 3. 3. Figure 5. 10 tutorial entity. Xilinx Spartan-3E Project Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 38 2. Double-click on kcpsm3 in the Sources window, to display the source code for kcpsm3. vhd.A close up of the code for the kspsm3 entity is shown in Figure 5. 11. Note that this corresponds to the KCPSM3 cram of Figures 3. 1 and 3. 2. Figure 5. 11 kcpsm3 entity. Xilinx Spartan-3E Project Navigato r Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 39 5. 5 Adding a top_level Entity VHDL code still needs to be written to tie together the kcpsm3 and tutorial entities, and also to interface with the Spartan-3E board. We will create a file called top_level. vhd for this purpose. 1. Select ProjectNew Source as shown in Figure 5. 12. The New Source Wizard will appear. Figure 5. 2 Adding a source file to the project. 2. Select Source Type as VHDL Module. 3. Enter the file name as top_level, and enter the location of the file (same as the project location entered earlier. 4. Verify that the Add to project box is checked. shown in Figure 5. 13. The New Source Wizard should now appear as Xilinx Spartan-3E Project Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 40 Figure 5. 13 New Source Wizard, Select Source Type. 5. Click Next to go to the Define Module window. 6. Define the ports (inputs and outputs of the design) by entering the information as shown in Figure 5. 14.These ports are described as follows switches will be an input consisting of 8 bits, and will be connected with the 4 slide switches and 4 push buttons on the Spartan-3E. clk will be an input consisting of 1 bit, and will be connected to the clock input. LEDs will be an output consisting of 8 bits, and will be connected with the LEDs on the Spartan-3E. Xilinx Spartan-3E Project Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 41 Figure 5. 14 New Source Wizard, Define Module. 7. Click Next to move to the Summary page, as shown in Figure 5. 15. Xilinx Spartan-3E Project Navigator Version 14. Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 42 Figure 5. 15 New Source Wizard, Summary. 9. Click Finish to exit the New Source Wizard. As shown in Figure 5. 16, top_level will now appear in the Sources window. Double-clicking on top_level in the Sources window will display the file, top_le vel. vhd in a tab. Xilinx Spartan-3E Project Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 43 top_level in Sources window Figure 5. 16 top_level in the Sources window. Xilinx Spartan-3E Project Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 4 5. 6 Editing the top_level Entity 1. Double-click on top_level in the Sources window to display the file, top_level. vhd in a tab. The code for top_level. vhd is shown in Figure 5. 17. entity architecture Figure 5. 17 top_level. vhd, as displayed in Project Navigator, before editing. The code in Figure 5. 17 contains an entity and an architecture section. The entity section defines the inputs and outputs of this hardware block. In this case these have been automatically added using the New Source Wizard. The architecture section still needs to be written for this module. 2. deputize the architecture block in Figure 5. 7 with the code in Figure 5. 18(a) and (b). Th is code is a trimmed down version of the Initial Design for the Spartan-3E FPGA Starter Kit Board (the original design shipped with the board), downloaded from 7. For reference the complete code for top_level. vhd is listed in Appendix A. Note that where VDHL code is listed in this tutorial, the same colour coding as Project Navigator is used, to assist with readability. 3. Save the file by selecting File Save from the main menu. Xilinx Spartan-3E Project Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 45 rchitecture Behavioral of top_level is declaration of KCPSM3 (always use this declaration to call up PicoBlaze core) component kcpsm3 port (address out std_logic_vector(9 downto 0) instruction in std_logic_vector(17 downto 0) port_id out std_logic_vector(7 downto 0) write_strobe out std_logic out_port out std_logic_vector(7 downto 0) read_strobe out std_logic in_port in std_logic_vector(7 downto 0) interrupt in std_logic interrupt_a ck out std_logic reset in std_logic clk in std_logic) end component declaration of program memory (here you will specify the entity name as your . psm prefix name) component tutorial port (address in std_logic_vector(9 downto 0) instruction out std_logic_vector(17 downto 0) clk in std_logic) end component Signals used to connect PicoBlaze core to program memory and I/O logic sign up address std_logic_vector(9 downto 0) charge instruction std_logic_vector(17 downto 0) maneuver port_id std_logic_vector(7 downto ) signal out_port std_logic_vector(7 downto 0) signal in_port std_logic_vector(7 downto 0) signal write_strobe std_logic signal read_strobe std_logic signal interrupt_ack std_logic signal reset std_logic the following input is assigned an inactive value since it is unused in this example signal interrupt std_logic =0 Start of circuit description begin Instantiating the PicoBlaze core processor kcpsm3 port symbolize (address = address, instruction = in struction, port_id = port_id, write_strobe = write_strobe, Figure 5. 18(a) Architecture of top_level. vhd, part 1. Xilinx Spartan-3E Project Navigator Version 14. 3 Tutorial 2 Introduction to Using the PicoBlaze Microcontroller 46 ut_port = out_port, read_strobe = read_strobe, in_port = in_port, interrupt = interrupt, interrupt_ack = interrupt_ack, reset = reset, clk = clk) Instantiating the program memory program tutorial port map (address = address, instruction = instruction, clk = clk) Connect I/O of PicoBlaze - KCPSM3 Define input ports - The inputs connect via a pipelined multiplexer input_ports process(clk) begin if clkevent and clk=1 then case port_id(1 downto 0) is read simple toggle switches and buttons at address 00 hex when 00 = in_port instruction, port_id = port_id, write_strobe = write_strobe, out_port = out_port, read_strobe = read_strobe, in_port = in_port, interrupt = interrupt, interrupt_ack = interrupt_ack, reset = reset, clk = clk) Instantiating the