Hi Ashish, once again, thank you very much for your help.
I understood the problem. I moved the codec read/wirte code into a DSP/BIOS task. This is the code:
#include <std.h> #include <clk.h> #include <idl.h> #include <log.h> #include <sem.h> #include <swi.h> #include <tsk.h> #include "hellocfg.h" #include "stdio.h" #include "usbstk5505.h" #include "aic3204.h" #include "PLL.h" #include "stereo.h" Int16 left_input; Int16 right_input; Int16 left_output; Int16 right_output; Int16 mono_input; #define SAMPLES_PER_SECOND 48000 unsigned long int i = 0; Void main() { // ========================= audio loopback init ===================== USBSTK5505_init( ); // Initialize BSL pll_frequency_setup(100); // Initialize PLL aic3204_hardware_init(); // nitialise hardware interface and I2C for code aic3204_init(); // Initialise the AIC3204 codec //Setup sampling frequency and 30dB gain for microphone set_sampling_frequency_and_gain(SAMPLES_PER_SECOND, 30); // =================================================================== } Void funTSK0(){ LOG_printf(&trace, "TSK0-init"); for ( i = 0 ; i < SAMPLES_PER_SECOND * 20 ;i++ ){ aic3204_codec_read(&left_input, &right_input); // Configured for one interrupt per two channels. mono_input = stereo_to_mono(left_input, right_input); left_output = left_input; right_output = right_input; aic3204_codec_write(left_output, right_output); TSK_disable(); IDL_run(); TSK_enable(); } LOG_printf(&trace, "TSK0-end"); }
Now, RTA->CPU Load works in real time:
I put this codes in my task function funTSK0() to call the idle function and updated the load figures:
TSK_disable();
IDL_run();
TSK_enable();
(inside the "for" loop)
RTA->CPU Load works fine now, but is my code correct?
You told me to change my code to an interrupt based routine that blocks on a semaphore posted by the interrupt handler. I'm new on DSP, and I'm still trying to understand how to code this rotine. The Rulph Chassaing book named "DSP Applications Using C and the TMS320C6x DSK" shows some code snippets like this:
interrupt void c_int11(){
...
}
void main() {
...
while(1); //infinite loop
}
And some comments saying that the c_int11() is a callback function for interrupt # 11, which occurs every time a new sample is ready for processing. Is it the way to implement a interrupt routine? Is there some material about this to TMS320C5535?
Thank you so much
Antonio