/****************************************************************
*                                                               *
* Copyright (C) 1991-2003 Celoxica Ltd. All rights reserved.    *
*                                                               *
*****************************************************************
*                                                               *
* Project   :   PAL                                             *
* Date      :   31 JAN 2003                                     *
* File      :   reverb.hcc                                      *
* Author    :   Matthew Aubury (MA)                             *
* Contributors:                                                 *
*                                                               *
* Description:                                                  *
*    Simple audio reverb.                                       *
*                                                               *
* Date         Version  Author  Reason for change               *
*                                                               *
* 29 OCT 2002    1.00    MA     Created                         *
*                                                               *
****************************************************************/
 

#include <stdlib.hch>
#include "pal_master.hch"

#include "config.hch"
#include "debug.hch"
#include "fft.hch"
#include "runfft.hch"

#include "presets.hch"

/*
 * Forward declarations
 */

static macro expr ClockRate = PAL_ACTUAL_CLOCK_RATE;
#if HARDWARE_MULTIPLY
//input buffer
ram signed 18 audio_buffer_in[256] with { block = "BlockRAM"};
//output buffer
ram signed 18 audio_buffer_out[128] with { block = "BlockRAM"};	
#else
//input buffer
ram signed 16 audio_buffer_in[256] with { block = "BlockRAM"};
//output buffer
ram signed 16 audio_buffer_out[128] with { block = "BlockRAM"};	
#endif
//EQ settings for the FFT
ram unsigned 4 EQ_info[128] with { block = "BlockRAM"};	
//EQ settings received from the display
mpram 
{
  ram unsigned 4 write[768];	
  rom unsigned 4 read[768];	
}EQ_level with { block = "BlockRAM"};	

mpram 
{
  ram unsigned 7 write[256];	
  rom unsigned 7 read[256];	
}fft_info with { block = "BlockRAM"};

#if HARDWARE_MULTIPLY
signed 18 *audioptr_in1,*audioptr_in2,*audioptr_in3,*audioptr_in4;
signed 18 *audioptr_out1,*audioptr_out2;
signed 18 *audioptr_temp;
#else
signed 16 *audioptr_in1,*audioptr_in2,*audioptr_in3,*audioptr_in4;
signed 16 *audioptr_out1,*audioptr_out2;
signed 16 *audioptr_temp;
#endif
unsigned 3 active_preset;

shared expr preset_address = (0@(active_preset-1))<<7;

void LoadPresets()
{
  unsigned 16 temp;
  unsigned 10 count;
  unsigned 8 index;
  
  count=0;
  do
  {
    par
    {
	temp = presets[index];
	index++;
    }
    par { EQ_level.write[count] = temp[7:4]; count++; }
    par { EQ_level.write[count] = temp[3:0]; count++; }
    par { EQ_level.write[count] = temp[15:12]; count++; }
    par { EQ_level.write[count] = temp[11:8]; count++; }
  } while (count<768);

}

/*
 * FFT routine
 */
macro proc RunFFT (AudioIn, AudioOut)
{
	signed 18 sample;
	unsigned 6 sample_count;
	unsigned 8 i,cycle;
	unsigned 4 eqinfo;

	unsigned 1 FFT_Sync, first;
	macro expr OW = PalAudioOutGetMaxDataWidthCT ();
	macro expr IW = PalAudioInGetMaxDataWidthCT  ();
	signed LeftNew, RightNew;
	signed Output_sample;

	ram unsigned 6 input[64];
	active_preset = 3;

  	//pointers for double and quadruple buffering:
  	audioptr_in1=&audio_buffer_in[0];
  	audioptr_in2=&audio_buffer_in[64];
  	audioptr_in3=&audio_buffer_in[128];
  	audioptr_in4=&audio_buffer_in[192];

  	audioptr_out1=&audio_buffer_out[0];
  	audioptr_out2=&audio_buffer_out[64];

  	FFT_Sync=0;

	LoadPresets();
	first = 1;
par
{
	for(;;)
	{
		if (FFT_Sync)	//if 64 samples are read from ADC...
		{
			par
			{
				// switch pointers 
	    			audioptr_in1 = audioptr_in2;
				audioptr_in2 = audioptr_in3;
				audioptr_in3 = audioptr_in4;
				audioptr_in4 = audioptr_in1;
				
				audioptr_out1 = audioptr_out2;
				audioptr_out2 = audioptr_out1;
				FFT_Sync = 0;
			}
		
			// FFT calculation
			perform_fft(audioptr_in1);
			
#if 1			
	      		for(i=0;i<NUMBER_OF_FREQUENCIES;i++)	  
        		{
				eqinfo = EQ_level.read[preset_address+(0@i)];
	      			EQ_info[i<-7] = eqinfo;
				if(first)
				{
					print_string("eqinfo: "):
					print_hex_value(eqinfo);
					print_eol();
					first = 0;
				}
		    	}
			


			// set volume of each individual frequency bar (equalizer)
			equalize_audio(&EQ_info[0], &fft_info.write[0]);
   		   	
#endif			// inverse FFT calculation
			perform_ifft(audioptr_out1);
			
/*
			for (i = 0; i != 64; i++)
			{
				sample = audioptr_in1[i];
				audioptr_out1[i] = sample;
			}
*/		
    		}
		else
			delay;
	}	

	for(sample_count=0;;)//store the samples in the inputbuffer
	{
		if (!FFT_Sync)
		{
			par
			{
				seq
				{
					PalAudioInRead(AudioIn, &LeftNew, &RightNew);
#if HARDWARE_MULTIPLY 					
					audioptr_in1[sample_count] = LeftNew;//drop 2 LSB's
#else
					audioptr_in1[sample_count] = (LeftNew\\2);//drop 2 LSB's
#endif
					sample_count++; 
    					if (!sample_count) 
					{
						FFT_Sync = 1; 
					}
				}
				seq
				{
					Output_sample = audioptr_out2[sample_count];
				}
			}
		}
		else
		{
			delay;
		}
	}
	for(;;)
	{
		PalAudioOutWrite(AudioOut,(signed OW)(Output_sample @ 0),(signed OW)(Output_sample @ 0));
	}
}//end par
}// end function