Lab 0: hardware introduction  (Page 2/6)

Step 2: log in

Use the network ID and password provided to log into the PC at your laboratory station.

When you log in, two shared networked drives should be mapped to the computer: the W: drive, which contains your own private network work directory, and the V: drive, where the necessary files for ECE 420 are stored. Be sure to save any files that you use for thecourse to the W: drive. Temporary files may be stored in the C:\TEMP directory; however, since files stored on the C: drive are accessible to any user, are local to each computer, and may be erased atany time, do not store course files on the C: drive. On the V: drive, the directories v:\ece420\54kx\dsplib\ and c:\ece420\54x\dsptools\ contain the files necessary to assemble and test code on the TI DSP evaluationboards.

Although you may want to work exclusively in one or the other of lab-partners' network account, you should besure that both partners have copies of the lab assignment assembly code.

The development environment

The evaluation board is controlled by the PC through the JTAG interface (XDS510PP) using the application Code ComposerStudio. This development environment allows the user to download, run, and debug code assembled on the PC. Workthrough the steps below to familiarize yourself with the debugging environment and real-time system using the providedFIR filter code (Steps 3, 4 and 5), then verify the filter's frequency response with the subsequent MATLAB exercises (Steps6 and 7).

Step 3: assemble filter code

Before you can execute and test the provided FIR filter code, you must assemble the source file. First, bring up a DOS prompt window and create a new directory to hold the files, and then copy them into your directory:

• w:
• mkdir lab0
• cd lab0
• copy v:\ece420\54x\dsplib\filter.asm .
• copy v:\ece420\54x\dsplib\coef.asm .

Next, assemble the filter code by typing asm filter at the DOS prompt. The assembling process first includes the FIR filtercoefficients (stored in coef.asm ) into the assembly file filter.asm , then compiles the result to produce an output file containing the executablebinary code, filter.out .

Step 4: verify filter execution

With your filter code assembled, double-click on the Code Composer icon to open the debugging environment. Beforeloading your code, you must reset the DSP board and initialize the processor mode status register ( PMST ). To reset the board, select the Reset option from the Debug menu in the Code Composer application.

Once the board is reset, select the CPU Registers option from the View menu, then select CPU Register . This will open a sub-window at the bottom of the Code Composer applicationwindow that displays several of the DSP registers. Look for the PMST register; it must be set to the hexadecimal value FFE0 to have the DSP evaluation board work correctly. If it is not setcorrectly, change the value of the PMST register by double-clicking on the value and making the appropriate change in the Edit Register window that comes up.