signal_processing_vorlage/software/signal_processing/rand.c

#include "system/task_rand.h"
#include "system/hardware_task.h"
#include "system/data_channel.h"
#include "system/float_word.h"

#include <stdio.h>

int task_rand_run( void * data )
{

	rand_config * task = ( rand_config * ) data;


	uint32_t data_channel_base = task->base.sink;

	float seed = task->seed;		//1.3
	float abs_min = task->abs_min;		//0.125
	float abs_max = task->abs_max;		//9.0

	float_word random_number;
	random_number.value = seed;

	uint32_t mask_bit_0 = 0x1;
	uint32_t mask_bit_1 = 0x2;
	uint32_t mask_bit_21 = 0x200000;
	uint32_t mask_bit_31 = 0x80000000;

	uint32_t exponent = 0;
	uint32_t shifted_exponent = 0;
	uint32_t shifted = 0;
	uint32_t shifted_modifiziert = 0;

	data_channel_clear( data_channel_base );

	for(uint32_t i = 0; i < DATA_CHANNEL_DEPTH; ++i)
	{

		//Bits extrahieren:
		uint32_t bit_0 = (random_number.word & mask_bit_0) >> 0;
		uint32_t bit_1 = (random_number.word & mask_bit_1) >> 1;
		uint32_t bit_21 = (random_number.word & mask_bit_21) >> 21;
		uint32_t bit_31 = (random_number.word & mask_bit_31) >> 31;

		//XOR:
		uint32_t xor_result = bit_0 ^ bit_1 ^ bit_21 ^ bit_31;

		//Shifted:
		shifted = random_number.word >> 1;

		//shifted &= ~(0x80000000);
		shifted |= (xor_result << 31);

		printf("%08x %08x %d \n", random_number.word, shifted, xor_result);

		//Skalierung:
#if 1
		exponent = (shifted >> 23) & 0xFF;
		if(exponent & (1 << 7)){
			exponent &= (0b10000001);
		}else{
			exponent |= (0b01111100);
		}


		shifted_modifiziert = shifted;
		shifted_exponent = exponent << 23;
		shifted_modifiziert &= 0x807FFFFF;
		shifted_modifiziert |= shifted_exponent;
#endif

		random_number.word = shifted_modifiziert;
		data_channel_write( data_channel_base, random_number.word );
		random_number.word = shifted;

	}


	return 0;
}