DShotRMT - ESP32 Library (Rewrite for ESP-IDF 5)

A modern, robust C++ library for generating DShot signals on the ESP32 using the new ESP-IDF 5 RMT encoder API (rmt_tx.h / rmt_rx.h).
Supports all standard DShot modes (150, 300, 600) and features continuous frame transmission with configurable pause.
Now with BiDirectional DShot support and advanced command management!

The legacy version (using the old rmt.h API) is still available in the oldAPI branch.

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🚀 Features

• All DShot Modes: DSHOT150, DSHOT300 (default), DSHOT600, (DSHOT1200)
• BiDirectional DShot: Experimental support for RPM feedback
• Advanced Command Manager: High-level API for ESC configuration and control
• Command Sequences: Predefined initialization and calibration sequences
• Continuous Frames: Independent timed, Hardware signal generation
• Configurable Pause: Ensures ESCs can reliably detect frame boundaries
• Simple API: Easy integration into your Arduino or ESP-IDF project

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📦 Installation

Clone this repository and add it to your Arduino libraries or ESP-IDF components.

git clone https://github.com/derdoktor667/DShotRMT.git

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⚡ Quick Start

Basic Usage (DShotRMT)

#include <DShotRMT.h>

// Create motor instance
DShotRMT motor(17, DSHOT300);

void setup() {
    Serial.begin(115200);
    motor.begin();
}

void loop() {
    motor.sendThrottle(1000);  // Send throttle value
    delay(20);
}

Advanced Usage (DShotCommandManager)

#include <DShotRMT.h>
#include <DShotCommandManager.h>

// Create motor and command manager instances
DShotRMT motor(17, DSHOT300);
DShotCommandManager cmdManager(motor);

void setup() {
    Serial.begin(115200);
    motor.begin();
    cmdManager.begin();
    
    // Execute initialization sequence
    cmdManager.executeInitSequence();
}

void loop() {
    // Your main code here
}

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🎛️ DShotCommandManager API

The DShotCommandManager provides a high-level interface for ESC control and configuration:

Motor Control

• stopMotor() - Stop motor immediately
• set3DMode(bool enable) - Enable/disable 3D mode
• setSpinDirection(bool reversed) - Set motor spin direction
• saveSettings() - Save current settings to ESC

LED Control (BLHeli32 only)

• setLED(uint8_t led_number, bool state) - Control ESC LEDs (0-3)

Beacon Functions

• activateBeacon(uint8_t beacon_number) - Activate motor beeping (1-5)

Telemetry

• setExtendedTelemetry(bool enable) - Enable/disable extended telemetry
• requestESCInfo() - Request ESC information

Command Sequences

• executeInitSequence() - Basic ESC initialization
• executeCalibrationSequence() - ESC calibration sequence
• executeSequence(sequence, length) - Custom command sequences

Utility Functions

• getCommandName(command) - Get command name as string
• isValidCommand(command) - Validate command
• printStatistics() - Print execution statistics
• resetStatistics() - Reset execution counters

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📚 Examples

1. Basic DShot Control

Use the dshot300.ino example for simple throttle control.

2. Advanced Command Management

Use the command_manager.ino example for interactive ESC control:

=== DShot Command Manager Menu ===
Basic Commands:
  1 - Stop Motor
  2 - Activate Beacon 1
  3 - Set Normal Spin Direction
  4 - Set Reversed Spin Direction
  5 - Enable 3D Mode
  6 - Disable 3D Mode
  7 - Save Settings
  8 - Turn LED 0 ON
  9 - Turn LED 0 OFF

Sequences:
  i - Execute Initialization Sequence
  c - Execute Calibration Sequence

Advanced:
  cmd <number> - Send DShot command (0 - 47)
  throttle <value> - Set throttle (48 - 2047)
  throttle 0 - Stop sending throttle

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📚 DShot Protocol Overview

DShot transmits 16-bit packets to brushless ESCs:

• 11 bits: Throttle value
• 1 bit: Telemetry request
• 4 bits: Checksum (CRC)

Data is sent MSB-first. Pulse timing depends on the selected DShot mode.

DSHOT	Bitrate	TH1	TH0	Bit Time (µs)	Frame Time (µs)
150	150 kbit/s	5.00	2.50	6.67	~106.72
300	300 kbit/s	2.50	1.25	3.33	~53.28
600	600 kbit/s	1.25	0.625	1.67	~26.72

Each frame is followed by a pause to help ESCs detect separate frames.

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🔒 Checksum Calculation

The checksum is calculated over the first 12 bits (throttle + telemetry):

crc = (value ^ (value >> 4) ^ (value >> 8)) & 0x0F;

Bidirectional DSHOT

Bidirectional DSHOT (sometimes called "inverted DSHOT") inverts the signal level:
A logical '1' is low, and a '0' is high. This signals the ESC to send telemetry packets back.

Bidirectional CRC:

crc = (~(value ^ (value >> 4) ^ (value >> 8))) & 0x0F;

Note: Bidirectional DShot is experimental. Further hardware testing is needed.

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🛠️ ESP32 RMT Peripheral

The RMT (Remote Control) peripheral generates accurate, hardware-timed signals for controlling external devices.
Perfect for DShot:

• Utilizes latest ESP-IDF APIs
• Hardware-timed pulses
• CPU-independent
• Loop mode with inter-frame pause
• Reliable under system load

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📝 Core API Reference

DShotRMT Class

• DShotRMT(gpio_num_t gpio, dshot_mode_t mode, bool isBidirectional)
• uint16_t begin()
• bool sendThrottle(uint16_t throttle)
• bool sendCommand(uint16_t command)
• uint16_t getERPM() - Get eRPM (bidirectional mode only)
• uint32_t getMotorRPM(uint8_t magnet_count) - Convert to motor RPM

DShotCommandManager Class

• DShotCommandManager(DShotRMT &dshot_instance)
• bool begin()
• dshot_command_result_t sendCommand(dshot_commands_t command, uint16_t repeat_count = 1)
• dshot_command_result_t sendCommandWithDelay(dshot_commands_t command, uint16_t repeat_count, uint32_t delay_ms)

All command methods return a dshot_command_result_t structure containing:

• bool success - Command execution status
• uint32_t execution_time_us - Execution time in microseconds
• const char* error_message - Error description

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🎯 DShot Commands

The library supports all standard DShot commands:

Command	Value	Description
MOTOR_STOP	0	Stop motor
BEACON1-5	1-5	Motor beeping
ESC_INFO	6	Request ESC information
SPIN_DIRECTION_1/2	7-8	Set spin direction
3D_MODE_OFF/ON	9-10	3D mode control
SAVE_SETTINGS	12	Save settings to ESC
EXTENDED_TELEMETRY_ENABLE/DISABLE	13-14	Telemetry control
LED0-3_ON/OFF	22-29	LED control (BLHeli32)
AUDIO_STREAM_MODE	30	KISS audio mode
SILENT_MODE	31	KISS silent mode

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📖 References

• DSHOT – the missing Handbook
• DSHOT in the Dark
• ESP32 Technical Reference Manual

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📄 License

MIT License – see LICENSE

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👤 Author

Wastl Kraus
GitHub: @derdoktor667
Website: wir-sind-die-matrix.de