Theory

Sawtooth waves have an interesting mix of practice and theory. In practice, they are extremely simple. In their simplest form, they consist of an alternating sequence of increasing the amplitude and low state; e.g. increment voltage to reach peak and out the 0v.

The same increment / zero logic here we implented in experiment. For step by step duration the voltage is incremented , when it reached it peak, then 0v voltege is out.

Finally Sawtooth wave is generated and plotted in code composer studio Graph.

Procedure for build a project on Sawtooth Wave Generation using TMS320C6745 DSP

1. Open Code Composer Studio v4 .

2. In WorkSpace Launcher.

• BROWSE → Select the project location and make one new folder, MAKE NEW FOLDER → Type the Workspace name, OK → OK.

3. FILE ⇒ NEW ⇒ CCS PROJECT

• Project name: Type your project name.

• Tick use default location. → NEXT

• Project type C6000.

• Tick Debug And Release. → NEXT → NEXT.

• Output type: Executable.

• Device Variant : generic – TMS320C6745.

• Device Endianness : little

• Code Generation Tools: TI v6.1.12.

• Run time support library: automatic.

• Target content: none. →FINISH

4.FILE ⇒ NEW ⇒ SOURCE FILE

• Source file: Type your projectname.c( .c extension is must ).

• Type the program.

• FILE → SAVE.

5. Paste the following board library files in workspace location.

• Common folder (contains header files)

• Gel folder (contains gel file)

• Library folder(contains library files)

6. Paste the Linker file in the project location.(linker file is available in cd)

Note: Those folders and linker file are availble at cd.

7. PROJECT ⇒ PROPERTIES ⇒ C/C++ BUILD → BASIC OPTION

• Target processor version(–silicon version, -mv) : 6400+ OK.

• IN C/C++ BUILD, → INCLUDE OPTIONS (Add dir to #include search path(–include_path,-I)) select the add icon and add the following three path by indivdually – “${Diag}../../common/header” – “${XDAIS_CG_ROOT}/packages/ti/xdais” – “${C6000_CSL_CG_ROOT}/include”

8. FILE ⇒ NEW ⇒ TARGET CONFIGURATION FILE

• file name: projectname. ccxml (.ccxml extension is must)

• Connection: Texas Instrument XDS100 v1 USB Emulator.

• Device: TMS320C6745. (Tick the TMS320C6745)→ SAVE → TARTGET CONFIGURATION → C674X_0 → BROWSE, browse the workspace location, open the gel folder and select the GEL file. → OPEN → SAVE.

9. In C/C++ Project window, Right click the project ⇒ REBUILD PROJECT.

10. Connections

• Connect the usb cable, PC to TMS320C6745 KIT.

• Connect the 5v adapter.

• Power on the kit.

11. TARGET ⇒ DEBUG ACTIVE PROJECT.

12. TARGET ⇒ RUN.(wait few seconds generate samples)

13. TARGET ⇒ HALT.

14. TOOLS ⇒ GRAPH ⇒ SINGLE TIME

• Acquirstion buffer size : 500

• Index increment : 1

• Start address : 0xC0000000.

• Display data size : 500 → Ok.

Program for Sawtooth Wave Generation using TMS320C6745 DSP

 
#include 

#include 

void main()

{

int *Sawtooth;

int i=0,j=0;

Sawtooth = (int *)0xC0000000;

while(1)

{

for(i=0;i<100;i++)

{

j=j+1;

*Sawtooth++ = j;

}

j=0;

i=0;

*Sawtooth++ = j;

}

}

Strong

Thus, the Sawtooth waveform was generated and samples is stored at memory location(0xC0000000).