40 lines
1.1 KiB
C
40 lines
1.1 KiB
C
#include "system/task_rand.h"
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#include "system/hardware_task.h"
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#include "system/data_channel.h"
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#include "system/float_word.h"
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int task_rand_run(void *task)
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{
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rand_config *config = (rand_config *)task;
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uint32_t data_channel_base = config->base.sink;
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data_channel_clear(data_channel_base);
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float_word seed_fw = { .value = config->seed };
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uint32_t lfsr = seed_fw.word;
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for (uint32_t i = 0; i < DATA_CHANNEL_DEPTH; ++i) {
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uint32_t sign = (lfsr >> 31) & 0x1u;
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uint32_t mant = lfsr & 0x007FFFFFu; // 23 Bit Mantisse
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uint32_t exp_rand = (lfsr >> 23) & 0xFFu; // 8 Bit Exponent
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uint32_t exp_new;
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if (exp_rand & 0x80u) {
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exp_new = 0x80u | (exp_rand & 0x01u);
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} else {
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exp_new = 0x7Cu | (exp_rand & 0x03u);
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}
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float_word out;
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out.word = (sign << 31) | (exp_new << 23) | mant;
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data_channel_write(data_channel_base, out.word);
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uint32_t fb = ((lfsr >> 31) ^ (lfsr >> 21) ^ (lfsr >> 1) ^ (lfsr >> 0)) & 0x1u;
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lfsr = (lfsr << 1) | fb;
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}
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return 0;
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}
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