mirror of https://github.com/markqvist/MMDVM.git
Update P25 to match YSF demodulator, work in progress.
Jonathan Naylor
parent
609c2ead53
commit
9d1fbcfc73
428
P25RX.cpp
428
P25RX.cpp
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@ -1,5 +1,5 @@
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/*
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* Copyright (C) 2016,2017 by Jonathan Naylor G4KLX
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* Copyright (C) 2009-2017 by Jonathan Naylor G4KLX
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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@ -16,239 +16,194 @@
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* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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*/
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// #define WANT_DEBUG
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#define WANT_DEBUG
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#include "Config.h"
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#include "Globals.h"
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#include "P25RX.h"
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#include "Utils.h"
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const unsigned int BUFFER_LENGTH = 200U;
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const q15_t SCALING_FACTOR = 18750; // Q15(0.55)
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const uint32_t PLLMAX = 0x10000U;
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const uint32_t PLLINC = PLLMAX / P25_RADIO_SYMBOL_LENGTH;
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const uint32_t INC = PLLINC / 32U;
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const uint8_t SYNC_SYMBOL_ERRS = 0U;
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const uint8_t SYNC_BIT_START_ERRS = 2U;
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const uint8_t SYNC_BIT_RUN_ERRS = 4U;
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const unsigned int MAX_SYNC_FRAMES = 3U + 1U;
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const uint8_t MAX_SYNC_SYMBOLS_ERRS = 2U;
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const uint8_t MAX_SYNC_BYTES_ERRS = 3U;
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const uint8_t BIT_MASK_TABLE[] = {0x80U, 0x40U, 0x20U, 0x10U, 0x08U, 0x04U, 0x02U, 0x01U};
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#define WRITE_BIT1(p,i,b) p[(i)>>3] = (b) ? (p[(i)>>3] | BIT_MASK_TABLE[(i)&7]) : (p[(i)>>3] & ~BIT_MASK_TABLE[(i)&7])
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#define READ_BIT1(p,i) (p[(i)>>3] & BIT_MASK_TABLE[(i)&7])
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const uint16_t NOENDPTR = 9999U;
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const unsigned int MAX_SYNC_FRAMES = 4U + 1U;
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CP25RX::CP25RX() :
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m_pll(0U),
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m_prev(false),
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m_state(P25RXS_NONE),
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m_bitBuffer(0x00U),
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m_symbols(),
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m_outBuffer(),
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m_buffer(NULL),
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m_bufferPtr(0U),
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m_symbolPtr(0U),
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m_bitBuffer(),
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m_buffer(),
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m_bitPtr(0U),
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m_dataPtr(0U),
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m_endPtr(NOENDPTR),
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m_syncPtr(NOENDPTR),
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m_minSyncPtr(NOENDPTR),
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m_maxSyncPtr(NOENDPTR),
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m_maxCorr(0),
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m_lostCount(0U),
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m_centre(0),
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m_threshold(0),
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m_centre(),
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m_centreVal(0),
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m_centreBest(0),
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m_threshold(),
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m_thresholdVal(0),
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m_thresholdBest(0),
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m_averagePtr(0u),
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m_rssiAccum(0U),
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m_rssiCount(0U)
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{
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m_buffer = m_outBuffer + 1U;
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}
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void CP25RX::reset()
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{
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m_pll = 0U;
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m_prev = false;
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m_state = P25RXS_NONE;
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m_bitBuffer = 0x00U;
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m_bufferPtr = 0U;
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m_symbolPtr = 0U;
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m_lostCount = 0U;
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m_centre = 0;
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m_threshold = 0;
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m_rssiAccum = 0U;
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m_rssiCount = 0U;
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m_state = P25RXS_NONE;
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m_dataPtr = 0U;
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m_bitPtr = 0U;
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m_maxCorr = 0;
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m_averagePtr = 0U;
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m_endPtr = NOENDPTR;
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m_syncPtr = NOENDPTR;
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m_minSyncPtr = NOENDPTR;
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m_maxSyncPtr = NOENDPTR;
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m_centreVal = 0;
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m_thresholdVal = 0;
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m_lostCount = 0U;
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m_rssiAccum = 0U;
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m_rssiCount = 0U;
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}
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void CP25RX::samples(const q15_t* samples, const uint16_t* rssi, uint8_t length)
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void CP25RX::samples(const q15_t* samples, uint16_t* rssi, uint8_t length)
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{
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for (uint16_t i = 0U; i < length; i++) {
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for (uint8_t i = 0U; i < length; i++) {
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q15_t sample = samples[i];
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m_rssiAccum += rssi[i];
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m_rssiCount++;
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bool bit = samples[i] < 0;
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m_bitBuffer[m_bitPtr] <<= 1;
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if (sample < 0)
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m_bitBuffer[m_bitPtr] |= 0x01U;
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if (bit != m_prev) {
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if (m_pll < (PLLMAX / 2U))
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m_pll += INC;
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else
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m_pll -= INC;
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}
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m_buffer[m_dataPtr] = sample;
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m_prev = bit;
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if (m_state == P25RXS_NONE)
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processNone(sample);
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else
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processData(sample);
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m_pll += PLLINC;
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m_dataPtr++;
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if (m_dataPtr >= P25_LDU_FRAME_LENGTH_SAMPLES)
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m_dataPtr = 0U;
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if (m_pll >= PLLMAX) {
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m_pll -= PLLMAX;
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if (m_state == P25RXS_NONE)
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processNone(samples[i]);
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else
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processData(samples[i]);
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}
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m_bitPtr++;
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if (m_bitPtr >= P25_RADIO_SYMBOL_LENGTH)
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m_bitPtr = 0U;
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}
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}
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void CP25RX::processNone(q15_t sample)
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{
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m_symbolBuffer <<= 1;
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if (sample < 0)
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m_symbolBuffer |= 0x01U;
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bool ret = correlateSync(true);
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if (ret) {
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m_rssiAccum = 0U;
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m_rssiCount = 0U;
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m_symbols[m_symbolPtr] = sample;
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// Fuzzy matching of the data sync bit sequence
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if (countBits32((m_symbolBuffer & P25_SYNC_SYMBOLS_MASK) ^ P25_SYNC_SYMBOLS) <= SYNC_SYMBOL_ERRS) {
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q15_t max = -16000;
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q15_t min = 16000;
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for (uint8_t i = 0U; i < P25_SYNC_LENGTH_SYMBOLS; i++) {
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q15_t val = m_symbols[i];
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if (val > max)
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max = val;
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if (val < min)
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min = val;
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}
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q15_t centre = (max + min) >> 1;
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q31_t v1 = (max - centre) * SCALING_FACTOR;
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q15_t threshold = q15_t(v1 >> 15);
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uint16_t ptr = m_symbolPtr + 1U;
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if (ptr >= P25_SYNC_LENGTH_SYMBOLS)
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ptr = 0U;
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for (uint8_t i = 0U; i < P25_SYNC_LENGTH_SYMBOLS; i++) {
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q15_t sample = m_symbols[ptr] - centre;
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if (sample < -threshold) {
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m_bitBuffer <<= 2;
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m_bitBuffer |= 0x01U;
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} else if (sample < 0) {
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m_bitBuffer <<= 2;
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m_bitBuffer |= 0x00U;
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} else if (sample < threshold) {
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m_bitBuffer <<= 2;
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m_bitBuffer |= 0x02U;
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} else {
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m_bitBuffer <<= 2;
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m_bitBuffer |= 0x03U;
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}
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ptr++;
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if (ptr >= P25_SYNC_LENGTH_SYMBOLS)
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ptr = 0U;
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}
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// Fuzzy matching of the data sync bit sequence
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if (countBits64((m_bitBuffer & P25_SYNC_BITS_MASK) ^ P25_SYNC_BITS) <= SYNC_BIT_START_ERRS) {
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DEBUG5("P25RX: sync found in None min/max/centre/threshold", min, max, centre, threshold);
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for (uint8_t i = 0U; i < P25_SYNC_LENGTH_BYTES; i++)
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m_buffer[i] = P25_SYNC_BYTES[i];
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m_centre = centre;
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m_threshold = threshold;
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m_lostCount = MAX_SYNC_FRAMES;
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m_bufferPtr = P25_SYNC_LENGTH_BITS;
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m_state = P25RXS_DATA;
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m_rssiAccum = 0U;
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m_rssiCount = 0U;
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io.setDecode(true);
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io.setADCDetection(true);
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}
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io.setDecode(true);
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io.setADCDetection(true);
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}
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m_symbolPtr++;
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if (m_symbolPtr >= P25_SYNC_LENGTH_SYMBOLS)
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m_symbolPtr = 0U;
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if (m_dataPtr == m_endPtr) {
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for (uint8_t i = 0U; i < 16U; i++) {
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m_centre[i] = m_centreBest;
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m_threshold[i] = m_thresholdBest;
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}
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m_centreVal = m_centreBest;
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m_thresholdVal = m_thresholdBest;
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m_averagePtr = 0U;
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DEBUG4("P25RX: sync found in None pos/centre/threshold", m_syncPtr, m_centreVal, m_thresholdVal);
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uint16_t ptr = m_endPtr + P25_RADIO_SYMBOL_LENGTH + 1U;
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if (ptr >= P25_LDU_FRAME_LENGTH_SAMPLES)
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ptr -= P25_LDU_FRAME_LENGTH_SAMPLES;
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m_minSyncPtr = m_syncPtr + P25_LDU_FRAME_LENGTH_SAMPLES - 1U;
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if (m_minSyncPtr >= P25_LDU_FRAME_LENGTH_SAMPLES)
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m_minSyncPtr -= P25_LDU_FRAME_LENGTH_SAMPLES;
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m_maxSyncPtr = m_syncPtr + 1U;
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if (m_maxSyncPtr >= P25_LDU_FRAME_LENGTH_SAMPLES)
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m_maxSyncPtr -= P25_LDU_FRAME_LENGTH_SAMPLES;
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uint8_t frame[P25_LDU_FRAME_LENGTH_BYTES + 3U];
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samplesToBits(ptr, P25_LDU_FRAME_LENGTH_SYMBOLS, frame, 8U, m_centreVal, m_thresholdVal);
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frame[0U] = 0x01U;
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writeRSSILdu(frame);
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// Start the next frame
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::memset(frame, 0x00U, P25_LDU_FRAME_LENGTH_BYTES + 3U);
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m_state = P25RXS_DATA;
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m_maxCorr = 0;
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}
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}
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void CP25RX::processData(q15_t sample)
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{
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sample -= m_centre;
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if (sample < -m_threshold) {
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m_bitBuffer <<= 2;
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m_bitBuffer |= 0x01U;
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WRITE_BIT1(m_buffer, m_bufferPtr, false);
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m_bufferPtr++;
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WRITE_BIT1(m_buffer, m_bufferPtr, true);
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m_bufferPtr++;
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} else if (sample < 0) {
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m_bitBuffer <<= 2;
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m_bitBuffer |= 0x00U;
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WRITE_BIT1(m_buffer, m_bufferPtr, false);
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m_bufferPtr++;
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WRITE_BIT1(m_buffer, m_bufferPtr, false);
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m_bufferPtr++;
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} else if (sample < m_threshold) {
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m_bitBuffer <<= 2;
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m_bitBuffer |= 0x02U;
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WRITE_BIT1(m_buffer, m_bufferPtr, true);
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m_bufferPtr++;
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WRITE_BIT1(m_buffer, m_bufferPtr, false);
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m_bufferPtr++;
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if (m_minSyncPtr < m_maxSyncPtr) {
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if (m_dataPtr >= m_minSyncPtr && m_dataPtr <= m_maxSyncPtr)
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correlateSync(false);
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} else {
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m_bitBuffer <<= 2;
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m_bitBuffer |= 0x03U;
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WRITE_BIT1(m_buffer, m_bufferPtr, true);
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m_bufferPtr++;
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WRITE_BIT1(m_buffer, m_bufferPtr, true);
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m_bufferPtr++;
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if (m_dataPtr >= m_minSyncPtr || m_dataPtr <= m_maxSyncPtr)
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correlateSync(false);
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}
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// Search for an early sync to indicate an LDU following a header
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if (m_bufferPtr >= (P25_HDR_FRAME_LENGTH_BITS + P25_SYNC_LENGTH_BITS - 1U) && m_bufferPtr <= (P25_HDR_FRAME_LENGTH_BITS + P25_SYNC_LENGTH_BITS + 1U)) {
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// Fuzzy matching of the data sync bit sequence
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if (countBits64((m_bitBuffer & P25_SYNC_BITS_MASK) ^ P25_SYNC_BITS) <= SYNC_BIT_RUN_ERRS) {
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DEBUG2("P25RX: found LDU sync in Data, pos", m_bufferPtr - P25_SYNC_LENGTH_BITS);
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if (m_dataPtr == m_endPtr) {
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uint16_t ptr = m_endPtr + P25_RADIO_SYMBOL_LENGTH + 1U;
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if (ptr >= P25_LDU_FRAME_LENGTH_SAMPLES)
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ptr -= P25_LDU_FRAME_LENGTH_SAMPLES;
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m_outBuffer[0U] = 0x01U;
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serial.writeP25Hdr(m_outBuffer, P25_HDR_FRAME_LENGTH_BYTES + 1U);
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// Only update the centre and threshold if they are from a good sync
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if (m_lostCount == MAX_SYNC_FRAMES) {
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m_threshold[m_averagePtr] = m_thresholdBest;
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m_centre[m_averagePtr] = m_centreBest;
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m_rssiAccum = 0U;
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m_rssiCount = 0U;
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m_averagePtr++;
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if (m_averagePtr >= 16U)
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m_averagePtr = 0U;
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// Restore the sync that's now in the wrong place
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for (uint8_t i = 0U; i < P25_SYNC_LENGTH_BYTES; i++)
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m_buffer[i] = P25_SYNC_BYTES[i];
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// Find the average centre and threshold values
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m_centreVal = 0;
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m_thresholdVal = 0;
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for (uint8_t i = 0U; i < 16U; i++) {
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m_centreVal += m_centre[i];
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m_thresholdVal += m_threshold[i];
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}
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m_centreVal >>= 4;
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m_thresholdVal >>= 4;
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m_lostCount = MAX_SYNC_FRAMES;
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m_bufferPtr = P25_SYNC_LENGTH_BITS;
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DEBUG4("P25RX: sync found in Data (best) pos/centre/threshold", m_syncPtr, m_centreBest, m_thresholdBest);
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DEBUG4("P25RX: sync found in Data (val) pos/centre/threshold", m_syncPtr, m_centreVal, m_thresholdVal);
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m_minSyncPtr = m_syncPtr + P25_LDU_FRAME_LENGTH_SAMPLES - 1U;
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if (m_minSyncPtr >= P25_LDU_FRAME_LENGTH_SAMPLES)
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m_minSyncPtr -= P25_LDU_FRAME_LENGTH_SAMPLES;
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m_maxSyncPtr = m_syncPtr + 1U;
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if (m_maxSyncPtr >= P25_LDU_FRAME_LENGTH_SAMPLES)
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m_maxSyncPtr -= P25_LDU_FRAME_LENGTH_SAMPLES;
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}
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}
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// Only search for a sync in the right place +-2 symbols
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if (m_bufferPtr >= (P25_SYNC_LENGTH_BITS - 2U) && m_bufferPtr <= (P25_SYNC_LENGTH_BITS + 2U)) {
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// Fuzzy matching of the data sync bit sequence
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if (countBits64((m_bitBuffer & P25_SYNC_BITS_MASK) ^ P25_SYNC_BITS) <= SYNC_BIT_RUN_ERRS) {
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DEBUG2("P25RX: found sync in Data, pos", m_bufferPtr - P25_SYNC_LENGTH_BITS);
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m_lostCount = MAX_SYNC_FRAMES;
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m_bufferPtr = P25_SYNC_LENGTH_BITS;
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}
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}
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uint8_t frame[P25_LDU_FRAME_LENGTH_BYTES + 3U];
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samplesToBits(ptr, P25_LDU_FRAME_LENGTH_SYMBOLS, frame, 8U, m_centreVal, m_thresholdVal);
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// Send a data frame to the host if the required number of bits have been received
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if (m_bufferPtr == P25_LDU_FRAME_LENGTH_BITS) {
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// We've not seen a data sync for too long, signal RXLOST and change to RX_NONE
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m_lostCount--;
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if (m_lostCount == 0U) {
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@ -259,16 +214,118 @@ void CP25RX::processData(q15_t sample)
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serial.writeP25Lost();
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m_state = P25RXS_NONE;
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} else {
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m_outBuffer[0U] = m_lostCount == (MAX_SYNC_FRAMES - 1U) ? 0x01U : 0x00U;
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m_state = P25RXS_NONE;
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m_endPtr = NOENDPTR;
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} else {
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frame[0U] = m_lostCount == (MAX_SYNC_FRAMES - 1U) ? 0x01U : 0x00U;
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writeRSSILdu(m_outBuffer);
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writeRSSILdu(frame);
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// Start the next frame
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::memset(m_outBuffer, 0x00U, P25_LDU_FRAME_LENGTH_BYTES + 3U);
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m_bufferPtr = 0U;
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::memset(frame, 0x00U, P25_LDU_FRAME_LENGTH_BYTES + 3U);
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}
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m_maxCorr = 0;
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}
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}
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bool CP25RX::correlateSync(bool none)
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{
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if (countBits32((m_bitBuffer[m_bitPtr] & P25_SYNC_SYMBOLS_MASK) ^ P25_SYNC_SYMBOLS) <= MAX_SYNC_SYMBOLS_ERRS) {
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uint16_t ptr = m_dataPtr + P25_LDU_FRAME_LENGTH_SAMPLES - P25_SYNC_LENGTH_SAMPLES + P25_RADIO_SYMBOL_LENGTH;
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if (ptr >= P25_LDU_FRAME_LENGTH_SAMPLES)
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ptr -= P25_LDU_FRAME_LENGTH_SAMPLES;
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q31_t corr = 0;
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q15_t max = -16000;
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q15_t min = 16000;
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uint32_t mask = 0x00080000U;
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for (uint8_t i = 0U; i < P25_SYNC_LENGTH_SYMBOLS; i++, mask >>= 1) {
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bool b = (P25_SYNC_SYMBOLS & mask) == mask;
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if (m_buffer[ptr] > max)
|
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max = m_buffer[ptr];
|
||||
if (m_buffer[ptr] < min)
|
||||
min = m_buffer[ptr];
|
||||
|
||||
corr += b ? -m_buffer[ptr] : m_buffer[ptr];
|
||||
|
||||
ptr += P25_RADIO_SYMBOL_LENGTH;
|
||||
if (ptr >= P25_LDU_FRAME_LENGTH_SAMPLES)
|
||||
ptr -= P25_LDU_FRAME_LENGTH_SAMPLES;
|
||||
}
|
||||
|
||||
if (corr > m_maxCorr) {
|
||||
q15_t centre = (max + min) >> 1;
|
||||
|
||||
q31_t v1 = (max - centre) * SCALING_FACTOR;
|
||||
q15_t threshold = q15_t(v1 >> 15);
|
||||
|
||||
uint8_t sync[P25_SYNC_BYTES_LENGTH];
|
||||
|
||||
uint16_t ptr = m_dataPtr + P25_LDU_FRAME_LENGTH_SAMPLES - P25_SYNC_LENGTH_SAMPLES + P25_RADIO_SYMBOL_LENGTH;
|
||||
if (ptr >= P25_LDU_FRAME_LENGTH_SAMPLES)
|
||||
ptr -= P25_LDU_FRAME_LENGTH_SAMPLES;
|
||||
|
||||
if (none)
|
||||
samplesToBits(ptr, P25_SYNC_LENGTH_SYMBOLS, sync, 0U, centre, threshold);
|
||||
else
|
||||
samplesToBits(ptr, P25_SYNC_LENGTH_SYMBOLS, sync, 0U, m_centreVal, m_thresholdVal);
|
||||
|
||||
uint8_t errs = 0U;
|
||||
for (uint8_t i = 0U; i < P25_SYNC_BYTES_LENGTH; i++)
|
||||
errs += countBits8(sync[i] ^ P25_SYNC_BYTES[i]);
|
||||
|
||||
if (errs <= MAX_SYNC_BYTES_ERRS) {
|
||||
m_maxCorr = corr;
|
||||
m_thresholdBest = threshold;
|
||||
m_centreBest = centre;
|
||||
m_lostCount = MAX_SYNC_FRAMES;
|
||||
m_syncPtr = m_dataPtr;
|
||||
|
||||
m_endPtr = m_dataPtr + P25_LDU_FRAME_LENGTH_SAMPLES - P25_SYNC_LENGTH_SAMPLES - 1U;
|
||||
if (m_endPtr >= P25_LDU_FRAME_LENGTH_SAMPLES)
|
||||
m_endPtr -= P25_LDU_FRAME_LENGTH_SAMPLES;
|
||||
|
||||
return true;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
void CP25RX::samplesToBits(uint16_t start, uint16_t count, uint8_t* buffer, uint16_t offset, q15_t centre, q15_t threshold)
|
||||
{
|
||||
for (uint16_t i = 0U; i < count; i++) {
|
||||
q15_t sample = m_buffer[start] - centre;
|
||||
|
||||
if (sample < -threshold) {
|
||||
WRITE_BIT1(buffer, offset, false);
|
||||
offset++;
|
||||
WRITE_BIT1(buffer, offset, true);
|
||||
offset++;
|
||||
} else if (sample < 0) {
|
||||
WRITE_BIT1(buffer, offset, false);
|
||||
offset++;
|
||||
WRITE_BIT1(buffer, offset, false);
|
||||
offset++;
|
||||
} else if (sample < threshold) {
|
||||
WRITE_BIT1(buffer, offset, true);
|
||||
offset++;
|
||||
WRITE_BIT1(buffer, offset, false);
|
||||
offset++;
|
||||
} else {
|
||||
WRITE_BIT1(buffer, offset, true);
|
||||
offset++;
|
||||
WRITE_BIT1(buffer, offset, true);
|
||||
offset++;
|
||||
}
|
||||
|
||||
start += P25_RADIO_SYMBOL_LENGTH;
|
||||
if (start >= P25_LDU_FRAME_LENGTH_SAMPLES)
|
||||
start -= P25_LDU_FRAME_LENGTH_SAMPLES;
|
||||
}
|
||||
}
|
||||
|
||||
|
|
@ -292,3 +349,4 @@ void CP25RX::writeRSSILdu(uint8_t* ldu)
|
|||
m_rssiAccum = 0U;
|
||||
m_rssiCount = 0U;
|
||||
}
|
||||
|
||||
|
|
|
|||
34
P25RX.h
34
P25RX.h
|
|
@ -31,31 +31,37 @@ class CP25RX {
|
|||
public:
|
||||
CP25RX();
|
||||
|
||||
void samples(const q15_t* samples, const uint16_t* rssi, uint8_t length);
|
||||
void samples(const q15_t* samples, uint16_t* rssi, uint8_t length);
|
||||
|
||||
void reset();
|
||||
|
||||
private:
|
||||
uint32_t m_pll;
|
||||
bool m_prev;
|
||||
P25RX_STATE m_state;
|
||||
uint32_t m_symbolBuffer;
|
||||
uint64_t m_bitBuffer;
|
||||
q15_t m_symbols[P25_SYNC_LENGTH_SYMBOLS];
|
||||
uint8_t m_outBuffer[P25_LDU_FRAME_LENGTH_BYTES + 3U];
|
||||
uint8_t* m_buffer;
|
||||
uint16_t m_bufferPtr;
|
||||
uint16_t m_symbolPtr;
|
||||
uint32_t m_bitBuffer[P25_RADIO_SYMBOL_LENGTH];
|
||||
q15_t m_buffer[P25_LDU_FRAME_LENGTH_SAMPLES];
|
||||
uint16_t m_bitPtr;
|
||||
uint16_t m_dataPtr;
|
||||
uint16_t m_endPtr;
|
||||
uint16_t m_minSyncPtr;
|
||||
uint16_t m_maxSyncPtr;
|
||||
uint16_t m_syncPtr;
|
||||
q31_t m_maxCorr;
|
||||
uint16_t m_lostCount;
|
||||
q15_t m_centre;
|
||||
q15_t m_threshold;
|
||||
q15_t m_centre[16U];
|
||||
q15_t m_centreVal;
|
||||
q15_t m_centreBest;
|
||||
q15_t m_threshold[16U];
|
||||
q15_t m_thresholdVal;
|
||||
q15_t m_thresholdBest;
|
||||
uint8_t m_averagePtr;
|
||||
uint32_t m_rssiAccum;
|
||||
uint16_t m_rssiCount;
|
||||
|
||||
void processNone(q15_t sample);
|
||||
void processData(q15_t sample);
|
||||
void writeRSSILdu(uint8_t* data);
|
||||
bool correlateSync(bool none);
|
||||
void samplesToBits(uint16_t start, uint16_t count, uint8_t* buffer, uint16_t offset, q15_t centre, q15_t threshold);
|
||||
void writeRSSILdu(uint8_t* ldu);
|
||||
};
|
||||
|
||||
#endif
|
||||
|
||||
|
|
|
|||
10
YSFRX.h
10
YSFRX.h
|
|
@ -57,11 +57,11 @@ private:
|
|||
uint32_t m_rssiAccum;
|
||||
uint16_t m_rssiCount;
|
||||
|
||||
void processNone(q15_t sample);
|
||||
void processData(q15_t sample);
|
||||
bool correlateSync(bool none);
|
||||
void samplesToBits(uint16_t start, uint16_t count, uint8_t* buffer, uint16_t offset, q15_t centre, q15_t threshold);
|
||||
void writeRSSIData(uint8_t* data);
|
||||
void processNone(q15_t sample);
|
||||
void processData(q15_t sample);
|
||||
bool correlateSync(bool none);
|
||||
void samplesToBits(uint16_t start, uint16_t count, uint8_t* buffer, uint16_t offset, q15_t centre, q15_t threshold);
|
||||
void writeRSSIData(uint8_t* data);
|
||||
};
|
||||
|
||||
#endif
|
||||
|
|
|
|||
Loading…
Reference in New Issue