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...clean up

This commit is contained in:
Wastl Kraus 2025-07-31 13:16:58 +02:00
parent 338c679f94
commit dbfe3922f0
3 changed files with 71 additions and 43 deletions
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95
DShotRMT.cpp
View File

@ -19,7 +19,8 @@ const dshot_timing_t DSHOT_TIMINGS[] = {
//
DShotRMT::DShotRMT(gpio_num_t gpio, dshot_mode_t mode, bool is_bidirectional)
: _gpio(gpio), _mode(mode)
: _gpio(gpio)
, _mode(mode)
, _is_bidirectional(is_bidirectional)
, _timing_config(DSHOT_TIMINGS[mode])
, _rmt_tx_channel(nullptr)
@ -62,10 +63,9 @@ bool DShotRMT::begin()
return DSHOT_OK;
}
//
// Sets the throttle value and transmits
bool DShotRMT::setThrottle(uint16_t throttle)
{
// DShot Frame Container
dshot_packet_t packet = {};
@ -78,6 +78,32 @@ bool DShotRMT::setThrottle(uint16_t throttle)
{
return DSHOT_ERROR;
}
return DSHOT_OK;
}
// DShot Commands
bool DShotRMT::sendDShotCommand(uint16_t command)
{
// DShot Frame Container
dshot_packet_t packet = {};
if ((command < DSHOT_CMD_MOTOR_STOP) || command > DSHOT_CMD_MAX)
{
return DSHOT_ERROR;
}
// Create DShot packet
packet.throttle_value = command;
packet.telemetric_request = _is_bidirectional;
packet.checksum = _calculateCRC(packet);
if (!_sendDShotFrame(packet))
{
return DSHOT_ERROR;
}
return DSHOT_OK;
}
//
@ -203,40 +229,47 @@ uint16_t DShotRMT::_calculateCRC(const dshot_packet_t &packet)
return crc;
}
//
// Create a "raw" DShot Frame
uint16_t DShotRMT::_assembleDShotFrame(const dshot_packet_t &packet)
{
// Parses DShot Frame
// Check packet
uint16_t crc_calculated = _calculateCRC(packet);
uint16_t crc_in_packet = packet.checksum;
if (crc_calculated != crc_in_packet)
{
return DSHOT_ERROR;
}
// Parses DShot Packet
uint16_t data = (packet.throttle_value << 1) | packet.telemetric_request;
return (data << 4) | packet.checksum;
}
//
void DShotRMT::_encodeDShotFrame(const dshot_packet_t &packet, rmt_symbol_word_t *symbols)
// Converts DShot Frame
bool DShotRMT::_encodeDShotFrame(const dshot_packet_t &packet, rmt_symbol_word_t *symbols)
{
{
// Encoding to "raw" DShot Packet
uint16_t frame_bits = _assembleDShotFrame(packet);
// Encoding to "raw" DShot Packet
uint16_t frame_bits = _assembleDShotFrame(packet);
// Convert the parsed dshot frame to rmt_tx data
for (int i = 0; i < DSHOT_BITS_PER_FRAME; i++)
// Convert the parsed dshot frame to rmt_tx data
for (int i = 0; i < DSHOT_BITS_PER_FRAME; i++)
{
// Encode RMT symbols bitwise (MSB first) - tricky
bool bit = (frame_bits >> ((DSHOT_BITS_PER_FRAME - 1) - i)) & 0b0000000000000001;
if (_is_bidirectional)
{
// Encode RMT symbols bitwise (MSB first) - tricky
bool bit = (frame_bits >> (DSHOT_BITS_PER_FRAME - 1 - i)) & 0b0000000000000001;
if (_is_bidirectional)
{
symbols[i].level0 = 0;
symbols[i].duration0 = bit ? _timing_config.ticks_one_high : _timing_config.ticks_zero_high;
symbols[i].level1 = 1;
symbols[i].duration1 = bit ? _timing_config.ticks_one_low : _timing_config.ticks_zero_low;
}
else
{
symbols[i].level0 = 1;
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;
}
symbols[i].level0 = 0;
symbols[i].duration0 = bit ? _timing_config.ticks_one_high : _timing_config.ticks_zero_high;
symbols[i].level1 = 1;
symbols[i].duration1 = bit ? _timing_config.ticks_one_low : _timing_config.ticks_zero_low;
}
else
{
symbols[i].level0 = 1;
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;
}
}
}
@ -275,13 +308,13 @@ uint16_t DShotRMT::_decodeDShotFrame(const rmt_symbol_word_t *symbols, size_t sy
return data >> 1;
}
//
// Timer is ringing
bool DShotRMT::_timer_signal()
{
return (micros() - _last_transmission_time) >= _frame_time_us;
return ((micros() - _last_transmission_time) >= _frame_time_us);
}
//
// Timer restart
void DShotRMT::_timer_reset()
{
_last_transmission_time = micros();

8
DShotRMT.h
View File

@ -77,7 +77,7 @@ public:
// Sets the throttle value and transmits
bool setThrottle(uint16_t throttle);
// Sends a DShot Command
// Sends a valid DShot Command
bool sendDShotCommand(uint16_t command);
// Gets eRPM from ESC telemetry
@ -89,7 +89,7 @@ public:
//
gpio_num_t getGPIO() const { return _gpio; }
dshot_mode_t getDShotMode() const { return _mode; }
bool is_bidirectional() const { return _is_bidirectional; }
bool isBidirectional() const { return _is_bidirectional; }
private:
// --- Config ---
@ -117,14 +117,14 @@ private:
uint16_t _last_erpm;
unsigned long _last_transmission_time;
//
//
bool _initTXChannel();
bool _initRXChannel();
bool _initDShotEncoder();
uint16_t _calculateCRC(const dshot_packet_t &packet);
uint16_t _assembleDShotFrame(const dshot_packet_t &packet);
void _encodeDShotFrame(const dshot_packet_t &packet, rmt_symbol_word_t *symbols);
bool _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);

11
examples/dshot300/dshot300.ino
View File

@ -16,13 +16,11 @@ constexpr uint32_t USB_SERIAL_BAUD = 115200;
// Motor configuration
constexpr gpio_num_t MOTOR01_PIN = GPIO_NUM_17;
constexpr dshot_mode_t DSHOT_MODE = DSHOT300;
// BiDirectional DShot Support (default: false)
constexpr bool IS_BIDIRECTIONAL = false;
// Motor magnet count for RPM calculation
constexpr uint8_t MOTOR01_MAGNET_COUNT = 14;
// BiDirectional DShot Signal (default: false)
constexpr bool IS_BIDIRECTIONAL = false;
// Setup Motor Pin, DShot Mode and optional BiDirectional Support
DShotRMT motor01(MOTOR01_PIN, DSHOT_MODE, IS_BIDIRECTIONAL);
@ -41,9 +39,6 @@ void setup()
// Initialize DShot Signal
motor01.begin();
// Arm ESC with minimum throttle
motor01.setThrottle(DSHOT_THROTTLE_MIN);
USB_SERIAL.println("**********************");
USB_SERIAL.println("DShotRMT Demo started.");
USB_SERIAL.println("Enter a throttle value (48 – 2047):");