...logic improvements
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Wastl Kraus
parent
2a34960e02
commit
338c679f94
390
DShotRMT.cpp
390
DShotRMT.cpp
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@ -1,244 +1,288 @@
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/**
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/**
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* @file DShotRMT.cpp
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* @file DShotRMT.cpp
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* @brief DShot signal generation using ESP32 RMT with continuous repeat and pause between frames, including BiDirectional support
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* @brief DShot signal generation using ESP32 RMT with bidirectional support
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* @author Wastl Kraus
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* @author Wastl Kraus
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* @date 2025-06-11
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* @date 2025-06-11
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* @license MIT
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* @license MIT
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*/
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*/
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#include <DShotRMT.h>
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#include "DShotRMT.h"
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// --- DShotRMT Class ---
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// --- DShot Timings ---
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// This class provides an abstraction for sending and optionally receiving DShot frames.
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const dshot_timing_t DSHOT_TIMINGS[] = {
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// It uses ESP32's RMT peripheral for precise timing control, including BiDirectional RX.
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{0, 0, 0, 0, 0, 0}, // DSHOT_OFF
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{128, 64, 48, 24, 40, 16}, // DSHOT150
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{64, 32, 24, 12, 20, 8}, // DSHOT300
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{32, 16, 12, 6, 10, 4}, // DSHOT600
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{16, 8, 6, 3, 5, 2} // DSHOT1200
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};
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DShotRMT::DShotRMT(gpio_num_t gpio, dshot_mode_t mode, bool isBidirectional)
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//
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: _gpio(gpio), _mode(mode), _isBidirectional(isBidirectional)
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DShotRMT::DShotRMT(gpio_num_t gpio, dshot_mode_t mode, bool is_bidirectional)
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: _gpio(gpio), _mode(mode)
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, _is_bidirectional(is_bidirectional)
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, _timing_config(DSHOT_TIMINGS[mode])
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, _rmt_tx_channel(nullptr)
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, _rmt_rx_channel(nullptr)
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, _dshot_encoder(nullptr)
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, _last_erpm(0)
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, _last_transmission_time(0)
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{
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{
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// Fixed Timings for compatibility
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// Calculate frame time including switch time
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_frame_time = dshot_times.frameLength + DSHOT_SWITCH_TIME;
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_frame_time_us = _timing_config.frame_length_us + DSHOT_SWITCH_TIME;
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// DShot Frame answer padding
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// Double up frame time for bidirectional mode
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if (_isBidirectional)
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if (_is_bidirectional)
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{
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{
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_frame_time += _frame_time;
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_frame_time_us += _frame_time_us;
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}
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}
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}
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}
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// Initializes RMT TX and RX channels and encoder configuration
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//
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void DShotRMT::begin()
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bool DShotRMT::begin()
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{
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{
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// Configure RX RMT Channel for BiDirectional DShot
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if (!_initTXChannel())
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if (_isBidirectional)
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{
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{
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_rmt_rx_channel_config = {
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Serial.println("Failed to initialize TX channel");
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.gpio_num = _gpio,
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return DSHOT_ERROR;
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.clk_src = DSHOT_CLOCK_SRC_DEFAULT,
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.resolution_hz = DSHOT_RMT_RESOLUTION,
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.mem_block_symbols = DSHOT_SYMBOLS_SIZE,
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};
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if (rmt_new_rx_channel(&_rmt_rx_channel_config, &_rmt_rx_channel) != 0)
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{
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Serial.println("Failed to create RX channel");
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return;
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}
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if (rmt_enable(_rmt_rx_channel) != 0)
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{
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Serial.println("Failed to enable RX channel");
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return;
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}
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_receive_config.signal_range_min_ns = 300;
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_receive_config.signal_range_max_ns = 5000;
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}
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}
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// Configure TX RMT Channel
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if (!_initRXChannel() && _is_bidirectional)
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_rmt_tx_channel_config = {
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.gpio_num = _gpio,
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.clk_src = DSHOT_CLOCK_SRC_DEFAULT,
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.resolution_hz = DSHOT_RMT_RESOLUTION,
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.mem_block_symbols = DSHOT_SYMBOLS_SIZE,
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.trans_queue_depth = TX_BUFFER_SIZE};
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// Transmission configuration
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_transmit_config.loop_count = NULL;
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_transmit_config.flags.eot_level = _isBidirectional;
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if (rmt_new_tx_channel(&_rmt_tx_channel_config, &_rmt_tx_channel) != 0)
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{
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{
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Serial.println("Failed to create TX channel");
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Serial.println("Failed to initialize RX channel");
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return;
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return DSHOT_ERROR;
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}
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}
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if (rmt_enable(_rmt_tx_channel) != 0)
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if (!_initDShotEncoder())
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{
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{
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Serial.println("Failed to enable TX channel");
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Serial.println("Failed to initialize encoder");
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return;
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return DSHOT_ERROR;
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}
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}
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// Create copy encoder for raw symbol transmission
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return DSHOT_OK;
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if (!_dshot_encoder)
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{
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rmt_copy_encoder_config_t enc_cfg = {};
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if (rmt_new_copy_encoder(&enc_cfg, &_dshot_encoder) != 0)
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{
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Serial.println("Failed to create copy encoder");
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return;
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}
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}
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}
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}
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// Encodes and transmits a valid DShot throttle value (48 - 2047)
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//
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void DShotRMT::setThrottle(uint16_t throttle)
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bool DShotRMT::setThrottle(uint16_t throttle)
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{
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{
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// Simple timer
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static unsigned long last_time = NULL;
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//
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// DShot Frame Container
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dshot_packet_t packet = {};
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dshot_packet_t packet = {};
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packet.throttle_value = (constrain(throttle, DSHOT_THROTTLE_MIN, DSHOT_THROTTLE_MAX) & 0b0000011111111111);
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// Create DShot packet
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packet.telemetric_request = _isBidirectional;
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packet.throttle_value = constrain(throttle, DSHOT_THROTTLE_MIN, DSHOT_THROTTLE_MAX);
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packet.checksum = calculateCRC(packet);
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packet.telemetric_request = _is_bidirectional;
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packet.checksum = _calculateCRC(packet);
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// DShot transcoding
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if (!_sendDShotFrame(packet))
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rmt_symbol_word_t tx_symbols[DSHOT_BITS_PER_FRAME] = {};
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encodeDShotTX(packet, tx_symbols);
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// Ensure frame lenght for compatibility
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if (micros() - last_time >= _frame_time)
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{
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{
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// Transmit the packet
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return DSHOT_ERROR;
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if (rmt_transmit(_rmt_tx_channel, _dshot_encoder, tx_symbols, DSHOT_SYMBOLS_SIZE, &_transmit_config) != 0)
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{
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Serial.println("Failed to transmit DShot packet");
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return;
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}
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// Timestamp
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last_time = micros();
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}
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}
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}
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}
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// Receives and decodes a response frame from ESC containing eRPM info
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//
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uint32_t DShotRMT::getERPM()
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uint32_t DShotRMT::getERPM()
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{
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{
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if (_isBidirectional)
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if (!_is_bidirectional || !_rmt_rx_channel)
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{
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{
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if (_rmt_rx_channel == nullptr)
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{
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Serial.println("No bidirectional DShot support.");
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return _last_erpm;
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}
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// Try to receive a new frame
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if (!rmt_receive(_rmt_rx_channel, _rx_symbols, DSHOT_SYMBOLS_SIZE, &_receive_config))
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{
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Serial.println("No valid DShot frame received");
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return _last_erpm;
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}
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_last_erpm = decodeDShotRX(_rx_symbols, DSHOT_BITS_PER_FRAME);
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return _last_erpm;
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return _last_erpm;
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}
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}
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// No RX possible in non-bidirectional mode
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// Try to receive telemetry data
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if (!rmt_receive(_rmt_rx_channel, _rx_symbols, DSHOT_SYMBOLS_SIZE, &_receive_config))
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{
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return _last_erpm;
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}
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// Decode the response
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uint16_t new_erpm = _decodeDShotFrame(_rx_symbols, DSHOT_BITS_PER_FRAME);
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if (new_erpm != 0)
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{
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_last_erpm = new_erpm;
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}
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return _last_erpm;
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return _last_erpm;
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}
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}
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// Converts eRPM value to RPM using magnet count
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//
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uint32_t DShotRMT::getMotorRPM(uint8_t magnet_count)
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uint32_t DShotRMT::getMotorRPM(uint8_t magnet_count)
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{
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{
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uint8_t pole_count = magnet_count / 2;
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uint8_t pole_pairs = max(1, magnet_count / 2);
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if (pole_count == 0)
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return getERPM() / pole_pairs;
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pole_count = 1;
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return getERPM() / pole_count;
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}
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}
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// Calculates CRC for DShot packet
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//
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uint16_t DShotRMT::calculateCRC(dshot_packet_t dshot_packet)
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bool DShotRMT::_initTXChannel()
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{
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{
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uint16_t crc = (dshot_packet.throttle_value << 1) | (dshot_packet.telemetric_request);
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// --- RMT TX Config ---
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_tx_channel_config.gpio_num = _gpio;
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_tx_channel_config.clk_src = DSHOT_CLOCK_SRC_DEFAULT;
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_tx_channel_config.resolution_hz = DSHOT_RMT_RESOLUTION;
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_tx_channel_config.mem_block_symbols = DSHOT_SYMBOLS_SIZE;
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_tx_channel_config.trans_queue_depth = TX_BUFFER_SIZE;
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// CRC calculation for DShot (4 bits)
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_transmit_config.loop_count = 0;
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dshot_packet.checksum = ((crc ^ (crc >> 4) ^ (crc >> 8)) & 0b0000000000001111);
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// CRC is inverted for bidirectional DShot
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// ...it's a trap
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if (dshot_packet.telemetric_request)
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_transmit_config.flags.eot_level = _is_bidirectional ? 1 : 0;
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dshot_packet.checksum = (~dshot_packet.checksum) & 0b0000000000001111;
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return dshot_packet.checksum;
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// Creates and activate RMT TX Channel
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}
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if (rmt_new_tx_channel(&_tx_channel_config, &_rmt_tx_channel) != DSHOT_OK)
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// Assembles DShot packet (11 bit throttle + 1 bit telemetry request + 4 bit CRC)
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uint16_t DShotRMT::parseDShotPacket(const dshot_packet_t dshot_packet)
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{
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uint16_t raw = (((dshot_packet.throttle_value << 1) | (dshot_packet.telemetric_request)) & 0b0000111111111111);
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return (((raw << 4) | (dshot_packet.checksum)) & 0b1111111111111111);
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}
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// Converts a 16-bit packet into a valid DShot frame for RMT
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void DShotRMT::encodeDShotTX(dshot_packet_t dshot_packet, rmt_symbol_word_t *symbols)
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{
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// Encoding to "raw" DShot Packet
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uint16_t frame_bits = parseDShotPacket(dshot_packet);
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// Always start with the "first" bit
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size_t count = NULL;
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// Convert the parsed dshot frame to rmt_tx data
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for (int i = DSHOT_BITS_PER_FRAME - 1; i >= 0; i--)
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{
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{
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bool bit = (frame_bits >> i) & 0b0000000000000001;
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return DSHOT_ERROR;
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if (_isBidirectional)
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}
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return rmt_enable(_rmt_tx_channel) == 0;
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}
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//
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bool DShotRMT::_initRXChannel()
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{
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// --- RMT RX Config ---
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_rx_channel_config.gpio_num = _gpio;
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_rx_channel_config.clk_src = DSHOT_CLOCK_SRC_DEFAULT;
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_rx_channel_config.resolution_hz = DSHOT_RMT_RESOLUTION;
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_rx_channel_config.mem_block_symbols = DSHOT_SYMBOLS_SIZE;
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_receive_config.signal_range_min_ns = 300;
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_receive_config.signal_range_max_ns = 5000;
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// Create and activate RMT TX Channel
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if (rmt_new_rx_channel(&_rx_channel_config, &_rmt_rx_channel) != DSHOT_OK)
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{
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return DSHOT_ERROR;
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}
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return rmt_enable(_rmt_rx_channel) == 0;
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}
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//
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bool DShotRMT::_initDShotEncoder()
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{
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// Creates a dummy encoder
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rmt_copy_encoder_config_t encoder_config = {};
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return rmt_new_copy_encoder(&encoder_config, &_dshot_encoder) == 0;
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}
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//
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bool DShotRMT::_sendDShotFrame(const dshot_packet_t &packet)
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{
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//
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if (!_timer_signal())
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{
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return DSHOT_ERROR;
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}
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// Encodes packet directly into RMT Buffer
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rmt_symbol_word_t tx_symbols[DSHOT_BITS_PER_FRAME];
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_encodeDShotFrame(packet, tx_symbols);
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// Trigger RMT Transmit
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if (rmt_transmit(_rmt_tx_channel, _dshot_encoder, tx_symbols, DSHOT_SYMBOLS_SIZE, &_transmit_config) != 0)
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{
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Serial.println("Failed to transmit DShot packet");
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return DSHOT_ERROR;
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}
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_timer_reset();
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return DSHOT_OK;
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}
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//
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uint16_t DShotRMT::_calculateCRC(const dshot_packet_t &packet)
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{
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uint16_t data = (packet.throttle_value << 1) | packet.telemetric_request;
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uint16_t crc = (data ^ (data >> 4) ^ (data >> 8)) & 0b0000000000001111;
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// Invert CRC for bidirectional DShot
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if (packet.telemetric_request)
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{
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crc = (~crc) & 0b0000000000001111;
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}
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return crc;
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}
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//
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uint16_t DShotRMT::_assembleDShotFrame(const dshot_packet_t &packet)
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{
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// Parses DShot Frame
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uint16_t data = (packet.throttle_value << 1) | packet.telemetric_request;
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return (data << 4) | packet.checksum;
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}
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//
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void DShotRMT::_encodeDShotFrame(const dshot_packet_t &packet, rmt_symbol_word_t *symbols)
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{
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{
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// Encoding to "raw" DShot Packet
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uint16_t frame_bits = _assembleDShotFrame(packet);
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// Convert the parsed dshot frame to rmt_tx data
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for (int i = 0; i < DSHOT_BITS_PER_FRAME; i++)
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{
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{
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symbols[count].level0 = 0;
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// Encode RMT symbols bitwise (MSB first) - tricky
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symbols[count].duration0 = bit ? dshot_times.ticks_one_high : dshot_times.ticks_zero_high;
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bool bit = (frame_bits >> (DSHOT_BITS_PER_FRAME - 1 - i)) & 0b0000000000000001;
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symbols[count].level1 = 1;
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if (_is_bidirectional)
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symbols[count].duration1 = bit ? dshot_times.ticks_one_low : dshot_times.ticks_zero_low;
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{
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symbols[i].level0 = 0;
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symbols[i].duration0 = bit ? _timing_config.ticks_one_high : _timing_config.ticks_zero_high;
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symbols[i].level1 = 1;
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symbols[i].duration1 = bit ? _timing_config.ticks_one_low : _timing_config.ticks_zero_low;
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}
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else
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{
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symbols[i].level0 = 1;
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||||||
|
symbols[i].duration0 = bit ? _timing_config.ticks_one_high : _timing_config.ticks_zero_high;
|
||||||
|
symbols[i].level1 = 0;
|
||||||
|
symbols[i].duration1 = bit ? _timing_config.ticks_one_low : _timing_config.ticks_zero_low;
|
||||||
|
}
|
||||||
}
|
}
|
||||||
else
|
|
||||||
{
|
|
||||||
symbols[count].level0 = 1;
|
|
||||||
symbols[count].duration0 = bit ? dshot_times.ticks_one_high : dshot_times.ticks_zero_high;
|
|
||||||
symbols[count].level1 = 0;
|
|
||||||
symbols[count].duration1 = bit ? dshot_times.ticks_one_low : dshot_times.ticks_zero_low;
|
|
||||||
}
|
|
||||||
count++;
|
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
|
|
||||||
// Decodes a response frame from ESC containing eRPM info
|
//
|
||||||
uint16_t DShotRMT::decodeDShotRX(const rmt_symbol_word_t *symbols, uint32_t count)
|
uint16_t DShotRMT::_decodeDShotFrame(const rmt_symbol_word_t *symbols, size_t symbol_count)
|
||||||
{
|
{
|
||||||
uint16_t received_frame = DSHOT_NULL_PACKET;
|
uint16_t received_frame = 0;
|
||||||
|
|
||||||
// Build the frame bit by bit
|
// Decode each symbol to reconstruct the frame
|
||||||
for (size_t i = 0; i < DSHOT_BITS_PER_FRAME && i < count; ++i)
|
for (size_t i = 0; i < DSHOT_BITS_PER_FRAME; ++i)
|
||||||
{
|
{
|
||||||
bool bit = (symbols[i].duration0 < symbols[i].duration1);
|
bool bit = symbols[i].duration0 < symbols[i].duration1;
|
||||||
received_frame = (received_frame << 1) | bit;
|
received_frame = (received_frame << 1) | bit;
|
||||||
}
|
}
|
||||||
|
|
||||||
// Extract CRC and payload
|
// Extract payload and CRC
|
||||||
uint16_t payload = received_frame >> 4;
|
uint16_t data = received_frame >> 4;
|
||||||
uint8_t crc_received = received_frame & 0b0000000000001111;
|
uint8_t received_crc = received_frame & 0b0000000000001111;
|
||||||
|
|
||||||
// Calculate CRC for received frame
|
// Calculate CRC for received frame
|
||||||
uint8_t crc_calculated = (payload ^ (payload >> 4) ^ (payload >> 8)) & 0b0000000000001111;
|
uint8_t calculated_crc = (data ^ (data >> 4) ^ (data >> 8)) & 0b0000000000001111;
|
||||||
if (_isBidirectional)
|
if (_is_bidirectional)
|
||||||
crc_calculated = (~crc_calculated) & 0b0000000000001111;
|
|
||||||
|
|
||||||
// Check CRC
|
|
||||||
if (crc_received != crc_calculated)
|
|
||||||
{
|
{
|
||||||
Serial.println("RX - CRC check failed.");
|
calculated_crc = (~calculated_crc) & 0b0000000000001111;
|
||||||
return _last_erpm;
|
|
||||||
}
|
}
|
||||||
|
|
||||||
// Remove telemetry bit
|
// Compare CRC
|
||||||
return _last_erpm = payload >> 1;
|
if (received_crc != calculated_crc)
|
||||||
|
{
|
||||||
|
Serial.println("RX CRC Check failed");
|
||||||
|
return 0b0000000000000000;
|
||||||
|
}
|
||||||
|
|
||||||
|
// Remove telemetry bit and return eRPM
|
||||||
|
return data >> 1;
|
||||||
|
}
|
||||||
|
|
||||||
|
//
|
||||||
|
bool DShotRMT::_timer_signal()
|
||||||
|
{
|
||||||
|
return (micros() - _last_transmission_time) >= _frame_time_us;
|
||||||
|
}
|
||||||
|
|
||||||
|
//
|
||||||
|
void DShotRMT::_timer_reset()
|
||||||
|
{
|
||||||
|
_last_transmission_time = micros();
|
||||||
}
|
}
|
||||||
|
|
|
||||||
154
DShotRMT.h
154
DShotRMT.h
|
|
@ -1,6 +1,6 @@
|
||||||
/**
|
/**
|
||||||
* @file DShotRMT.h
|
* @file DShotRMT.h
|
||||||
* @brief DShot signal generation using ESP32 RMT with continuous repeat and pause between frames, including BiDirectional support
|
* @brief DShot signal generation using ESP32 RMT with bidirectional support
|
||||||
* @author Wastl Kraus
|
* @author Wastl Kraus
|
||||||
* @date 2025-06-11
|
* @date 2025-06-11
|
||||||
* @license MIT
|
* @license MIT
|
||||||
|
|
@ -15,23 +15,26 @@
|
||||||
#include <driver/rmt_rx.h>
|
#include <driver/rmt_rx.h>
|
||||||
|
|
||||||
static constexpr bool DSHOT_OK = 0;
|
static constexpr bool DSHOT_OK = 0;
|
||||||
static constexpr bool DSHOT_FAILED = 1;
|
static constexpr bool DSHOT_ERROR = 1;
|
||||||
|
|
||||||
// --- DShot Protocol Constants ---
|
// --- DShot Protocol Constants ---
|
||||||
static constexpr uint16_t DSHOT_THROTTLE_FAILSAVE = 0;
|
static constexpr uint16_t DSHOT_THROTTLE_FAILSAFE = 0;
|
||||||
static constexpr uint16_t DSHOT_THROTTLE_MIN = 48;
|
static constexpr uint16_t DSHOT_THROTTLE_MIN = 48;
|
||||||
static constexpr uint16_t DSHOT_THROTTLE_MAX = 2047;
|
static constexpr uint16_t DSHOT_THROTTLE_MAX = 2047;
|
||||||
|
|
||||||
// DShot Packet structure
|
static constexpr uint8_t DSHOT_BITS_PER_FRAME = 16;
|
||||||
typedef struct dshot_packet_s
|
static constexpr uint8_t DSHOT_SWITCH_TIME = 21;
|
||||||
{
|
static constexpr uint16_t DSHOT_NULL_PACKET = 0b0000000000000000;
|
||||||
uint16_t throttle_value : 11;
|
|
||||||
bool telemetric_request : 1;
|
|
||||||
uint16_t checksum : 4;
|
|
||||||
} dshot_packet_t;
|
|
||||||
|
|
||||||
// --- DShot Mode Selection ---
|
// --- RMT Config Constants ---
|
||||||
typedef enum dshot_mode_s
|
static constexpr rmt_clock_source_t DSHOT_CLOCK_SRC_DEFAULT = RMT_CLK_SRC_DEFAULT;
|
||||||
|
static constexpr uint32_t DSHOT_RMT_RESOLUTION = 10 * 1000 * 1000; // 10 MHz
|
||||||
|
static constexpr size_t TX_BUFFER_SIZE = DSHOT_BITS_PER_FRAME;
|
||||||
|
static constexpr size_t RX_BUFFER_SIZE = 32;
|
||||||
|
static constexpr size_t DSHOT_SYMBOLS_SIZE = 64;
|
||||||
|
|
||||||
|
// --- DShot Mode Select ---
|
||||||
|
typedef enum
|
||||||
{
|
{
|
||||||
DSHOT_OFF,
|
DSHOT_OFF,
|
||||||
DSHOT150,
|
DSHOT150,
|
||||||
|
|
@ -40,10 +43,18 @@ typedef enum dshot_mode_s
|
||||||
DSHOT1200
|
DSHOT1200
|
||||||
} dshot_mode_t;
|
} dshot_mode_t;
|
||||||
|
|
||||||
// --- DShot Timings ---
|
// --- DShot Packet Structure ---
|
||||||
typedef struct dshot_timing_s
|
typedef struct
|
||||||
{
|
{
|
||||||
uint16_t frameLength;
|
uint16_t throttle_value : 11;
|
||||||
|
bool telemetric_request : 1;
|
||||||
|
uint16_t checksum : 4;
|
||||||
|
} dshot_packet_t;
|
||||||
|
|
||||||
|
// --- DShot Timing Config ---
|
||||||
|
typedef struct
|
||||||
|
{
|
||||||
|
uint16_t frame_length_us;
|
||||||
uint16_t ticks_per_bit;
|
uint16_t ticks_per_bit;
|
||||||
uint16_t ticks_one_high;
|
uint16_t ticks_one_high;
|
||||||
uint16_t ticks_zero_high;
|
uint16_t ticks_zero_high;
|
||||||
|
|
@ -51,91 +62,72 @@ typedef struct dshot_timing_s
|
||||||
uint16_t ticks_one_low;
|
uint16_t ticks_one_low;
|
||||||
} dshot_timing_t;
|
} dshot_timing_t;
|
||||||
|
|
||||||
// DShot Pulse Length Settings
|
// --- DShot Timing Config ---
|
||||||
const dshot_timing_t dshot_timings[] = {
|
extern const dshot_timing_t DSHOT_TIMINGS[];
|
||||||
{0, 0, 0, 0, 0, 0}, // DSHOT_OFF
|
|
||||||
{128, 64, 48, 24, 40, 16}, // DSHOT150
|
|
||||||
{64, 32, 24, 12, 20, 8}, // DSHOT300
|
|
||||||
{32, 16, 12, 6, 10, 4}, // DSHOT600
|
|
||||||
{16, 8, 6, 3, 5, 2} // DSHOT1200
|
|
||||||
};
|
|
||||||
|
|
||||||
//
|
|
||||||
// --- DShotRMT Class ---
|
|
||||||
class DShotRMT
|
class DShotRMT
|
||||||
{
|
{
|
||||||
public:
|
public:
|
||||||
// Constructor: initializes configuration state
|
//
|
||||||
DShotRMT(gpio_num_t gpio, dshot_mode_t mode = DSHOT300, bool isBidirectional = false);
|
DShotRMT(gpio_num_t gpio, dshot_mode_t mode = DSHOT300, bool is_bidirectional = false);
|
||||||
|
|
||||||
// Initializes the RMT TX and RX channels
|
// --- Init RMT Module ---
|
||||||
void begin();
|
bool begin();
|
||||||
|
|
||||||
// Sets a new throttle value (48-2047) and sends it
|
// Sets the throttle value and transmits
|
||||||
void setThrottle(uint16_t throttle);
|
bool setThrottle(uint16_t throttle);
|
||||||
|
|
||||||
// Receives and decodes the latest value from ESC, if available
|
// Sends a DShot Command
|
||||||
|
bool sendDShotCommand(uint16_t command);
|
||||||
|
|
||||||
|
// Gets eRPM from ESC telemetry
|
||||||
uint32_t getERPM();
|
uint32_t getERPM();
|
||||||
|
|
||||||
|
// Converts eRPM to motor RPM
|
||||||
uint32_t getMotorRPM(uint8_t magnet_count);
|
uint32_t getMotorRPM(uint8_t magnet_count);
|
||||||
|
|
||||||
// Accessors for GPIO and DShot settings
|
//
|
||||||
gpio_num_t getGPIO() const { return _gpio; }
|
gpio_num_t getGPIO() const { return _gpio; }
|
||||||
dshot_mode_t getDShotMode() const { return _mode; }
|
dshot_mode_t getDShotMode() const { return _mode; }
|
||||||
|
bool is_bidirectional() const { return _is_bidirectional; }
|
||||||
// --- Configuration Parameters ---
|
|
||||||
gpio_num_t _gpio = GPIO_NUM_NC;
|
|
||||||
dshot_mode_t _mode = DSHOT_OFF;
|
|
||||||
bool _isBidirectional = false;
|
|
||||||
uint16_t _frame_time;
|
|
||||||
const dshot_timing_t &dshot_times = dshot_timings[_mode];
|
|
||||||
|
|
||||||
private:
|
private:
|
||||||
static constexpr uint8_t DSHOT_BITS_PER_FRAME = 16;
|
// --- Config ---
|
||||||
static constexpr uint8_t DSHOT_SWITCH_TIME = 42;
|
gpio_num_t _gpio;
|
||||||
|
dshot_mode_t _mode;
|
||||||
|
bool _is_bidirectional;
|
||||||
|
uint32_t _frame_time_us;
|
||||||
|
|
||||||
static constexpr uint16_t DSHOT_NULL_PACKET = 0b000000000000000;
|
// --- DShot Timings ---
|
||||||
static constexpr uint16_t DSHOT_FULL_PACKET = 0b111111111111111;
|
const dshot_timing_t &_timing_config;
|
||||||
static constexpr uint16_t NO_ERPM_SIGNAL = 0;
|
|
||||||
|
|
||||||
// RMT configuration parameters
|
// --- RMT Handles ---
|
||||||
static constexpr rmt_clock_source_t DSHOT_CLOCK_SRC_DEFAULT = RMT_CLK_SRC_DEFAULT;
|
rmt_channel_handle_t _rmt_tx_channel;
|
||||||
static constexpr uint32_t DSHOT_RMT_RESOLUTION = 10 * 1000 * 1000; // 10 MHz Clock
|
rmt_channel_handle_t _rmt_rx_channel;
|
||||||
|
rmt_encoder_handle_t _dshot_encoder;
|
||||||
|
|
||||||
static constexpr size_t TX_BUFFER_SIZE = DSHOT_BITS_PER_FRAME;
|
// --- RMT Config ---
|
||||||
static constexpr size_t RX_BUFFER_SIZE = 32;
|
rmt_tx_channel_config_t _tx_channel_config;
|
||||||
static constexpr size_t DSHOT_SYMBOLS_SIZE = 64;
|
rmt_rx_channel_config_t _rx_channel_config;
|
||||||
|
rmt_transmit_config_t _transmit_config;
|
||||||
|
rmt_receive_config_t _receive_config;
|
||||||
|
|
||||||
// Calculates the checksum for a DShot packet
|
// --- Buffers ---
|
||||||
uint16_t calculateCRC(dshot_packet_t dshot_packet);
|
rmt_symbol_word_t _rx_symbols[RX_BUFFER_SIZE];
|
||||||
|
uint16_t _last_erpm;
|
||||||
|
unsigned long _last_transmission_time;
|
||||||
|
|
||||||
// Parses the DShot packet (11 bit throttle + 1 bit telemetry request + 4 bit CRC)
|
//
|
||||||
uint16_t parseDShotPacket(const dshot_packet_t dshot_packet);
|
bool _initTXChannel();
|
||||||
|
bool _initRXChannel();
|
||||||
|
bool _initDShotEncoder();
|
||||||
|
|
||||||
// Converts a 16-bit DShot packet into RMT symbols
|
uint16_t _calculateCRC(const dshot_packet_t &packet);
|
||||||
void encodeDShotTX(dshot_packet_t dshot_packet, rmt_symbol_word_t *symbols);
|
uint16_t _assembleDShotFrame(const dshot_packet_t &packet);
|
||||||
|
void _encodeDShotFrame(const dshot_packet_t &packet, rmt_symbol_word_t *symbols);
|
||||||
|
uint16_t _decodeDShotFrame(const rmt_symbol_word_t *symbols, size_t symbol_count);
|
||||||
|
bool _sendDShotFrame(const dshot_packet_t &packet);
|
||||||
|
|
||||||
// Decodes the ESC answer
|
bool _timer_signal();
|
||||||
uint16_t decodeDShotRX(const rmt_symbol_word_t *symbols, uint32_t count);
|
void _timer_reset();
|
||||||
|
|
||||||
// --- DShot Packets Container ---
|
|
||||||
uint16_t _rx_packet = DSHOT_NULL_PACKET;
|
|
||||||
|
|
||||||
// --- RMT Channel Handles ---
|
|
||||||
rmt_channel_handle_t _rmt_rx_channel = nullptr;
|
|
||||||
rmt_channel_handle_t _rmt_tx_channel = nullptr;
|
|
||||||
rmt_rx_channel_config_t _rmt_rx_channel_config = {};
|
|
||||||
rmt_tx_channel_config_t _rmt_tx_channel_config = {};
|
|
||||||
|
|
||||||
// --- DShot RMT Encoder ---
|
|
||||||
rmt_encoder_handle_t _dshot_encoder = nullptr;
|
|
||||||
|
|
||||||
// --- RMT Configuration ---
|
|
||||||
rmt_receive_config_t _receive_config = {};
|
|
||||||
rmt_transmit_config_t _transmit_config = {};
|
|
||||||
|
|
||||||
// --- RMT Symbol Buffers ---
|
|
||||||
rmt_symbol_word_t _rx_symbols[RX_BUFFER_SIZE] = {};
|
|
||||||
|
|
||||||
// Stores the last valid eRPM received from the ESC
|
|
||||||
uint16_t _last_erpm = NULL;
|
|
||||||
};
|
};
|
||||||
|
|
|
||||||
Loading…
Reference in New Issue