Initial import

preamble.h

@@ -0,0 +1,53 @@
+/* 
+ * File:   preamble.h
+ * Author: nzasch
+ *
+ * Created on 12 gennaio 2017, 15.05
+ */
+
+#ifndef PREAMBLE_H
+#define	PREAMBLE_H
+
+#include <stdint.h>
+
+#ifdef __XC16
+#include <libq.h>
+#include <dsp.h>
+#else
+typedef int16_t _Q0_15;
+typedef int32_t _Q15_16;
+
+typedef _Q0_15 _Q15;
+typedef _Q15_16 _Q16;
+
+typedef int16_t fractional;
+#endif
+
+#include "modem_types.h"
+#include "demodulator.h"
+
+#define MODEM_PREAMBLE_LENGTH       13U
+#define MODEM_PREAMBLE_SQUELCH      0.7f // da 0 a 1
+
+// ((16000 ? 32) ? 20) ? 13 = 325
+#define MODEM_PREAMBLE_SEARCH_BUFF_SIZE         512U // circa (MODEM_PREAMBLE_LENGTH * MAX_BUFFERS_PER_SYMBOL) ma deve esere ^ di 2
+#define MODEM_PREAMBLE_SEARCH_BUFF_SIZE_MASK    (MODEM_PREAMBLE_SEARCH_BUFF_SIZE - 1)
+
+extern fractional sync_values_sequence[MODEM_PREAMBLE_LENGTH * MAX_BUFFERS_PER_SYMBOL]; ///< buffer che contiene il modello di sequenza
+extern _Q15_16 preamble_squelch_distance; ///< squelch pesato sulla lunghezza del preambolo
+
+// extern uint8_t modem_preamble_pending, modem_preamble_done;
+extern uint8_t modem_preamble_waiting, modem_post_preamble_delay, modem_post_preamble_timer;
+extern uint16_t BuffersPerPreamble;
+
+// protoz
+void modem_set_up_preamble(void);
+
+uint8_t modem_generate_preamble(uint8_t *ModulationSymbolsBuffer);
+void modem_generate_preamble_fingerprint(uint8_t *ModulationSymbolsBuffer, fractional *symbols_values_sequence, uint8_t values_per_symbol);
+
+_Q15_16 modem_get_preamble_max_correlation_index(uint8_t *ModulationSymbolsBuffer);
+uint8_t modem_detect_preamble(fractional insymbol);
+
+#endif	/* PREAMBLE_H */
+