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...testing rx callback

This commit is contained in:
Wastl Kraus 2025-08-31 11:43:48 +02:00
parent 04e84506c7
commit 5b02953516
3 changed files with 78 additions and 65 deletions
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117
DShotRMT.cpp
View File

@ -31,7 +31,8 @@ DShotRMT::DShotRMT(gpio_num_t gpio, dshot_mode_t mode, bool is_bidirectional)
_last_erpm(0),
_parsed_packet(0),
_packet{0},
_last_transmission_time(0)
_last_transmission_time(0),
_rx_queue(nullptr)
{
// Calculate frame timing including switch/pause time
_frame_timer_us = _timing_config.frame_length_us + DSHOT_SWITCH_TIME;
@ -61,15 +62,19 @@ uint16_t DShotRMT::begin()
}
// Initialize RX channel only if bidirectional mode is enabled
if (!_initRXChannel() && _is_bidirectional)
if (_is_bidirectional)
{
_dshot_log(RX_INIT_FAILED);
return DSHOT_ERROR;
if (!_initRXChannel())
{
_dshot_log(RX_INIT_FAILED);
return DSHOT_ERROR;
}
}
// Initialize DShot encoder
if (!_initDShotEncoder())
if (_initDShotEncoder() != DSHOT_OK)
{
_dshot_log(ENCODER_INIT_FAILED);
return DSHOT_ERROR;
}
@ -103,15 +108,22 @@ bool DShotRMT::_initTXChannel()
// Initialize RMT RX channel
bool DShotRMT::_initRXChannel()
{
// Create a queue to receive data from the RX callback
_rx_queue = xQueueCreate(1, sizeof(rmt_rx_done_event_data_t));
if (_rx_queue == nullptr)
{
return DSHOT_ERROR;
}
// Configure RX channel parameters
_rx_channel_config.gpio_num = _gpio;
_rx_channel_config.clk_src = DSHOT_CLOCK_SRC_DEFAULT;
_rx_channel_config.resolution_hz = DSHOT_RMT_RESOLUTION;
_rx_channel_config.mem_block_symbols = RX_BUFFER_SIZE;
// Configure reception parameters (TODO: determine optimal ranges)
// Configure reception parameters
_receive_config.signal_range_min_ns = 2;
_receive_config.signal_range_max_ns = 64;
_receive_config.signal_range_max_ns = 200;
// Create RMT RX channel
if (rmt_new_rx_channel(&_rx_channel_config, &_rmt_rx_channel) != DSHOT_OK)
@ -120,9 +132,30 @@ bool DShotRMT::_initRXChannel()
return DSHOT_ERROR;
}
// Register callback for reception
_rx_event_cbs.on_recv_done = _rmt_rx_done_callback;
if (rmt_rx_register_event_callbacks(_rmt_rx_channel, &_rx_event_cbs, _rx_queue) != DSHOT_OK)
{
_dshot_log(RX_INIT_FAILED);
return DSHOT_ERROR;
}
return (rmt_enable(_rmt_rx_channel) == DSHOT_OK);
}
// Callback for RMT reception completion
bool IRAM_ATTR DShotRMT::_rmt_rx_done_callback(rmt_channel_handle_t rx_chan, const rmt_rx_done_event_data_t *edata, void *user_data)
{
// Get the queue handle
QueueHandle_t rx_queue = (QueueHandle_t)user_data;
BaseType_t xHigherPriorityTaskWoken = pdFALSE;
// Send the event data to the queue
xQueueSendFromISR(rx_queue, edata, &xHigherPriorityTaskWoken);
return (xHigherPriorityTaskWoken == pdTRUE);
}
// Initialize DShot encoder
bool DShotRMT::_initDShotEncoder()
{
@ -160,8 +193,8 @@ bool DShotRMT::sendThrottle(uint16_t throttle)
last_throttle = throttle;
// Constrain throttle for transmission and send
uint16_t transmission_throttle = constrain(throttle, DSHOT_THROTTLE_MIN, DSHOT_THROTTLE_MAX);
_packet = _buildDShotPacket(transmission_throttle);
uint16_t new_throttle = constrain(throttle, DSHOT_THROTTLE_MIN, DSHOT_THROTTLE_MAX);
_packet = _buildDShotPacket(new_throttle);
return _sendDShotFrame(_packet);
}
@ -184,24 +217,22 @@ bool DShotRMT::sendCommand(uint16_t command)
uint16_t DShotRMT::getERPM()
{
// Check if bidirectional mode is enabled
if (!_is_bidirectional || !_rmt_rx_channel)
if (!_is_bidirectional)
{
_dshot_log(BIDIR_NOT_ENABLED);
return _last_erpm; // Return cached value
}
// Attempt to receive telemetry data
if (!rmt_receive(_rmt_rx_channel, _rx_symbols, TX_BUFFER_SIZE, &_receive_config))
{
_dshot_log(RX_RMT_MODULE_ERROR);
return _last_erpm;
}
// Decode telemetry frame
uint16_t new_erpm = _decodeDShotFrame(_rx_symbols);
if (new_erpm != 0)
rmt_rx_done_event_data_t rx_data;
// Wait for data from the RX callback for a certain timeout
if (xQueueReceive(_rx_queue, &rx_data, pdMS_TO_TICKS(DSHOT_RX_TIMEOUT_MS)) == pdTRUE)
{
_last_erpm = new_erpm;
// Decode the received symbols if a valid frame was received
if (rx_data.num_symbols > 0)
{
_last_erpm = _decodeDShotFrame(rx_data.received_symbols);
}
}
return _last_erpm;
@ -257,12 +288,18 @@ uint16_t DShotRMT::_calculateCRC(const dshot_packet_t &packet)
// Transmit DShot packet via RMT
uint16_t DShotRMT::_sendDShotFrame(const dshot_packet_t &packet)
{
// Check timing requirements
// Check timing requirements
if (!_timer_signal())
{
return DSHOT_ERROR;
}
// Enable RX reception before transmission for bidirectional mode
if (_is_bidirectional)
{
rmt_receive(_rmt_rx_channel, _rx_symbols, sizeof(_rx_symbols), &_receive_config);
}
// Encode DShot packet into RMT symbols
_encodeDShotFrame(packet, _tx_symbols);
@ -284,7 +321,7 @@ uint16_t DShotRMT::_sendDShotFrame(const dshot_packet_t &packet)
}
// Encode DShot packet into RMT symbol format (placed in IRAM for performance)
bool DShotRMT::_encodeDShotFrame(const dshot_packet_t &packet, rmt_symbol_word_t *symbols)
bool IRAM_ATTR DShotRMT::_encodeDShotFrame(const dshot_packet_t &packet, rmt_symbol_word_t *symbols)
{
// Parse packet to 16-bit format
_parsed_packet = _parseDShotPacket(packet);
@ -330,15 +367,11 @@ uint16_t DShotRMT::_decodeDShotFrame(const rmt_symbol_word_t *symbols)
}
// Extract data and CRC from received frame
uint16_t data = received_frame >> 4;
uint16_t received_crc = received_frame & 0b0000000000001111;
uint16_t data = received_frame >> 4;
// Calculate expected CRC
uint16_t calculated_crc = (data ^ (data >> 4) ^ (data >> 8)) & 0b0000000000001111;
if (_is_bidirectional)
{
calculated_crc = (~calculated_crc) & 0b0000000000001111; // Invert for bidirectional
}
// Validate CRC
if (received_crc != calculated_crc)
@ -352,7 +385,7 @@ uint16_t DShotRMT::_decodeDShotFrame(const rmt_symbol_word_t *symbols)
}
// Check if enough time has passed for next transmission
bool DShotRMT::_timer_signal()
bool IRAM_ATTR DShotRMT::_timer_signal()
{
uint32_t current_time = micros();
@ -419,29 +452,3 @@ void DShotRMT::printCpuInfo(Stream &output) const
output.printf("APB Freq = %lu Hz\n", getApbFrequency());
}
// Print debug values as stream
void DShotRMT::printDebugStream(Stream &output) const
{
// Debug Values as CSV format
output.print(_mode);
output.print(",");
output.print(_is_bidirectional);
output.print(",");
output.print(_packet.throttle_value);
output.print(",");
// The packet bitwise
for (int i = 15; i >= 0; --i)
{
if ((_parsed_packet >> i) & 1)
{
output.print("1");
}
else
{
output.print("0");
}
}
output.print("*/");
output.print("\n");
}

10
DShotRMT.h
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@ -21,12 +21,13 @@ constexpr auto DSHOT_THROTTLE_MAX = 2047;
constexpr auto DSHOT_BITS_PER_FRAME = 16;
constexpr auto DSHOT_SWITCH_TIME = 30;
constexpr auto DSHOT_NULL_PACKET = 0b0000000000000000;
constexpr auto DSHOT_RX_TIMEOUT_MS = 2;
// RMT Configuration Constants
constexpr auto DSHOT_CLOCK_SRC_DEFAULT = RMT_CLK_SRC_DEFAULT;
constexpr auto DSHOT_RMT_RESOLUTION = 10 * 1000 * 1000; // 10 MHz resolution
constexpr auto RMT_BUFFER_SIZE = DSHOT_BITS_PER_FRAME;
constexpr auto RX_BUFFER_SIZE = 128;
constexpr auto RX_BUFFER_SIZE = 64;
constexpr auto TX_BUFFER_SIZE = 64;
// DShot Mode Enumeration
@ -96,7 +97,6 @@ public:
// --- INFO ---
void printDshotInfo(Stream &output = Serial0) const;
void printCpuInfo(Stream &output = Serial0) const;
void printDebugStream(Stream &output = Serial0) const;
// --- DEPRECATED METHODS ---
[[deprecated("Use sendThrottle() instead")]]
@ -153,6 +153,11 @@ private:
bool IRAM_ATTR _timer_signal();
bool _timer_reset();
// -- CALLBACKS ---
QueueHandle_t _rx_queue;
rmt_rx_event_callbacks_t _rx_event_cbs;
static bool IRAM_ATTR _rmt_rx_done_callback(rmt_channel_handle_t rx_chan, const rmt_rx_done_event_data_t *edata, void *user_data);
// --- ERROR HANDLING & LOGGING ---
void _dshot_log(char *msg, Stream &output = Serial0) { output.println(msg); }
@ -169,4 +174,5 @@ private:
static constexpr char *COMMAND_NOT_VALID = "Not a valid DShot Command (0 - 47)!";
static constexpr char *BIDIR_NOT_ENABLED = "Bidirectional DShot support not enabled!";
static constexpr char *RX_RMT_MODULE_ERROR = "RX RMT module failure!";
static constexpr char *RX_RMT_RECEIVER_ERROR = "RX RMT receiver failure!";
};

14
examples/dshot300/dshot300.ino
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@ -68,18 +68,18 @@ void loop()
// Send the current throttle value
motor01.sendThrottle(throttle);
// Debug output
if (DEBUG)
{
motor01.printDebugStream();
return;
}
// Print motor stats every 2 seconds
if (millis() - last_stats_print >= 2000)
{
motor01.printDshotInfo();
// Get Motor RPM
if (IS_BIDIRECTIONAL)
{
uint32_t rpm = motor01.getMotorRPM(MOTOR01_MAGNET_COUNT);
USB_SERIAL.printf("Motor RPM: %u\n", rpm);
}
// Time Stamp
last_stats_print = millis();
}