This is a basic program from Rulph Chassing book
//Sine8_LED.c Sine generation with DIP switch control
#include "dsk6713_aic23.h" //support file for codec,DSK
Uint32 fs = DSK6713_AIC23_FREQ_8KHZ; //set sampling rate
short loop = 0; //table index
short gain = 10; //gain factor
short sine_table[8]={0,707,1000,707,0,-707,-1000,-707};//sine values
void main()
{
comm_poll(); //init DSK, codec, McBSP
DSK6713_LED_init(); //init LED from BSL
DSK6713_DIP_init(); //init DIP from BSL
while(1) //infinite loop
{
if(DSK6713_DIP_get(0)==0) //=0 if switch #0 pressed
{
DSK6713_LED_on(0); //turn LED #0 ON
output_sample(sine_table[loop]*gain); //output every Ts (SW0 on)
if (++loop > 7) loop = 0; //check for end of table
}
else DSK6713_LED_off(0); //LED #0 off
} //end of while (1)
} //end of main
We debug the program using rel time emulation and we are getting following
result. When DIP Switch # 0 is pressed, following sequence of statements are
executed,
DSK6713_LED_on(0); //turn LED #0 ON
output_sample(sine_table[loop]*gain); //output every Ts (SW0 on)
The last function is defined in "c6713dskinit.c" file. After this following
sequence of statements are executed,
short CHANNEL_data;
AIC_data.uint=0; //clear data structure
AIC_data.uint=out_data; //32-bit data -->data structure
CHANNEL_data=AIC_data.channel[RIGHT]; //swap left and right
channels
AIC_data.channel[RIGHT]=AIC_data.channel[LEFT];
AIC_data.channel[LEFT]=CHANNEL_data;
if (poll)
while(!MCBSP_xrdy(DSK6713_AIC23_DATAHANDLE)); //if ready to transmit
MCBSP_write(DSK6713_AIC23_DATAHANDLE,AIC_data.uint); //write/output
data
Now, at second last statement, program enters in infinite loop, That means McBSP
is never ready to transmit. Because of this we are not able to see sine wave on
DSO.
Please help me if anyone knows something about it.....
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