API Documentation

class crsf : public SerialIO 

#include <crsf.h>

A class for handling CRSF protocol communication.

Public Functions

explicit crsf(Stream *rxPort, int rxPin = -1, int txPin = -1, bool inverted = false)

Constructor for the CRSF class.

Parameters:

rxPort – Reference to the hardware serial port for RX communication.
rxPin – The RX pin number.
txPin – The TX pin number.
inverted – Whether the serial signal is inverted (true) or not (false).

virtual void begin() override: Initializes the CRSF communication.

virtual void processIncoming() override: Process incoming serial data and decode it.

virtual void getChannel(rc_channels_t *channelData) override

Retrieves the decoded RC channels from the received CRSF data.

Parameters:: channelData – Pointer to a crsf_channels_t struct where the decoded channel data will be stored.

uint8_t crc8(uint8_t *data, uint8_t len)

Private Members

crsf_channels_t _channelData

uint8_t _rxData[CRSF_MAX_PACKET_SIZE] = {0}

bool _headerDetected

uint8_t _rxIndex

uint8_t _buffer

struct crsf_channels_s

#include <crsf_protocol.h>

RC Packet Frame

Public Members

unsigned channel1

unsigned channel2

unsigned channel3

unsigned channel4

unsigned channel5

unsigned channel6

unsigned channel7

unsigned channel8

unsigned channel9

unsigned channel10

unsigned channel11

unsigned channel12

unsigned channel13

unsigned channel14

unsigned channel15

unsigned channel16

struct crsf_header_s

#include <crsf_protocol.h>

Heder of CRSF Packet

Public Members

uint8_t device_addr

uint8_t frame_size

uint8_t type

struct crsf_sensor_battery_s

#include <crsf_protocol.h>

Battery Voltage parameters

Public Members

uint32_t voltage

uint32_t current

uint32_t capacity

uint32_t remaining

struct crsf_sensor_gps_s

#include <crsf_protocol.h>

GPS parameters

Public Members

int32_t latitude

int32_t longitude

uint16_t groundspeed

uint16_t heading

uint16_t altitude

uint8_t satellites

struct crsfPayloadLinkstatistics_s

#include <crsf_protocol.h>

Payload Statics

Public Members

uint8_t uplink_RSSI_1

uint8_t uplink_RSSI_2

uint8_t uplink_Link_quality

int8_t uplink_SNR

uint8_t active_antenna

uint8_t rf_Mode

uint8_t uplink_TX_Power

uint8_t downlink_RSSI

uint8_t downlink_Link_quality

int8_t downlink_SNR

class fport : public SerialIO 

Public Functions

explicit fport(Stream *rxPort, int rxPin = -1, int txPin = -1, bool inverted = true)

virtual void begin() override: Initialize pins and set up the serial port.

virtual void processIncoming() override: Process incoming serial data and decode it.

virtual void getChannel(rc_channels_t *channelData) override

Retrieve the current channel data.

Note

The structure contains 16 channels, each represented as an 11-bit unsigned integer with a maximum value of 2047.

Parameters:: channelData – [out] Pointer to an rc_channels_t structure to store the retrieved channel data.

void crc()

Private Members

uint8_t _rxData[FPORT_MAX_PACKET_SIZE] = {0}

fport_channels_t _channelData

struct fport_channels_s

Public Members

unsigned channel1

unsigned channel2

unsigned channel3

unsigned channel4

unsigned channel5

unsigned channel6

unsigned channel7

unsigned channel8

unsigned channel9

unsigned channel10

unsigned channel11

unsigned channel12

unsigned channel13

unsigned channel14

unsigned channel15

unsigned channel16

unsigned dummy

unsigned failsafe

unsigned framelost

unsigned channel17

unsigned channel18

class ibus : public SerialIO 

#include <ibus.h>

A class for handling IBUS protocol communication.

Public Functions

explicit ibus(Stream *rxPort, int rxPin = -1, int txPin = -1, bool inverted = false)

Constructor for the IBUS class.

Parameters:

rxPort – Reference to the hardware serial port for RX communication.
rxPin – The RX pin number.
txPin – The TX pin number.
inverted – Whether the serial signal is inverted (true) or not (false).

virtual void begin() override: Initializes the IBUS communication.

virtual void processIncoming() override: Processes incoming IBUS data.

virtual void getChannel(rc_channels_t *channelData) override

Gets the decoded RC channels from the IBUS data.

Parameters:: channelData – Pointer to a rc_channels_t struct where the decoded channel data will be stored.

virtual void getChannel(ibus_channels_t *channelData) override

Gets the decoded RC channels from the IBUS data.

Parameters:: channelData – Pointer to a ibus_channels_t struct where the decoded channel data will be stored.

Private Functions

bool checkSum()

Private Members

ibus_channels_t _channelData

uint8_t _rxData[IBUS_MAX_PACKET_SIZE]: Buffer to store received IBUS data.

struct ibus_channels_s

Public Members

unsigned header

unsigned channel1

unsigned channel2

unsigned channel3

unsigned channel4

unsigned channel5

unsigned channel6

unsigned channel7

unsigned channel8

unsigned channel9

unsigned channel10

unsigned channel11

unsigned channel12

unsigned channel13

unsigned channel14

unsigned checksum

struct rc_channels_s

#include <SerialIO.h>

Structure representing 16 RC channels using 11-bit values.

Public Members

unsigned channel1

unsigned channel2

unsigned channel3

unsigned channel4

unsigned channel5

unsigned channel6

unsigned channel7

unsigned channel8

unsigned channel9

unsigned channel10

unsigned channel11

unsigned channel12

unsigned channel13

unsigned channel14

unsigned channel15

unsigned channel16

class sbus : public SerialIO 

#include <sbus.h>

A class for handling SBUS protocol communication.

Public Functions

explicit sbus(Stream *rxPort, int rxPin = -1, int txPin = -1, bool inverted = true)

Constructor for the SBUS class.

Parameters:

rxPort – Reference to the hardware serial port for RX communication.
rxPin – The RX pin number.
txPin – The TX pin number.
inverted – Whether the serial signal is inverted (true) or not (false).

virtual void begin() override: Initializes the SBUS communication.

virtual void processIncoming() override: Process incoming serial data and decode it.

virtual void getChannel(rc_channels_t *channelData) override

Gets the decoded RC channels from the SBUS data.

Parameters:: channelData – Pointer to a crsf_channels_t struct where the decoded channel data will be stored.

bool getFailsafe()

Gets the failsafe status from the SBUS data.

Returns:: True if failsafe is active, false otherwise.

bool getFramelost()

Gets the frame lost status from the SBUS data.

Returns:: True if frame lost is active, false otherwise.

bool getChannel17()

Gets the channel 17 status from the SBUS data.

Returns:: True if channel 17 is active, false otherwise.

bool getChannel18()

Gets the channel 18 status from the SBUS data.

Returns:: True if channel 18 is active, false otherwise.

bool getSerialConnectionStatus()

Gets the serial connection status.

Returns:: True if the connection is active, false if it has timed out.

Private Members

sbus_channels_t _channelData

uint8_t _rxData[SBUS_MAX_PACKET_SIZE]

struct sbus_channels_s

Public Members

unsigned header

unsigned channel1

unsigned channel2

unsigned channel3

unsigned channel4

unsigned channel5

unsigned channel6

unsigned channel7

unsigned channel8

unsigned channel9

unsigned channel10

unsigned channel11

unsigned channel12

unsigned channel13

unsigned channel14

unsigned channel15

unsigned channel16

unsigned dummy

unsigned failsafe

unsigned framelost

unsigned channel17

unsigned channel18

unsigned footer

class SerialIO

#include <SerialIO.h>

Class providing methods for initializing and decoding RC protocols.

Subclassed by crsf, fport, ibus, sbus

Public Functions

SerialIO(Stream *rxPort, int rxPin, int txPin, bool inverted)

Constructor to initialize the SerialIO class.

Parameters:

rxPort – Pointer to the hardware serial port to use.
rxPin – RX pin number.
txPin – TX pin number.
inverted – Set to true if the serial signal is inverted.

virtual ~SerialIO(): Virtual destructor.

virtual void begin() = 0: Initialize pins and set up the serial port.

virtual void processIncoming() = 0: Process incoming serial data and decode it.

virtual void getChannel(rc_channels_t *channelData) = 0

Retrieve the current channel data.

Note

The structure contains 16 channels, each represented as an 11-bit unsigned integer with a maximum value of 2047.

Parameters:: channelData – [out] Pointer to an rc_channels_t structure to store the retrieved channel data.

virtual void getChannel(ibus_channels_t *channelData)

Retrieve the current channel data using ibus_channels_t.

Parameters:: channelData – [out] Pointer to an ibus_channels_t structure to store the channel data.

Protected Functions

void leftShift(uint8_t arr[], size_t size)

Perform a left shift operation on the given byte array.

Parameters:

arr – Pointer to the byte array.
size – Size of the array.

void rightShift(uint8_t arr[], size_t size)

Perform a right shift operation on the given byte array.

Parameters:

arr – Pointer to the byte array.
size – Size of the array.

Protected Attributes

Stream *_rxPort: Pointer to the hardware serial port used for communication.

bool _inverted: Indicates whether the serial signal is inverted.

int _rxPin: RX pin number.

int _txPin: TX pin number.

uint32_t _lastPacketTime = 0: Timestamp of the last received packet.

bool _connectionTimeout = false: Indicates whether the connection has timed out.

file crsf_basic.ino

#include <SerialIO.h>

Functions

void setup()

void loop()

Variables

rc_channels_t channelData

crsf receiver & Serial

file crsf_basic.ino

#include <SerialIO.h>

Defines

CRSF_TX_PIN

CRSF_RX_PIN

Functions

void setup()

void loop()

Variables

rc_channels_t rcdata

crsf receiver & Serial1

file ibus_basic.ino

#include <SerialIO.h>

Functions

void setup()

void loop()

Variables

rc_channels_t channelData

ibus receiver & Serial

file ibus_basic.ino

#include <SerialIO.h>

Defines

IBUS_TX_PIN

IBUS_RX_PIN

Functions

void setup()

void loop()

Variables

rc_channels_t rcdata

ibus receiver & Serial1

file sbus_basic.ino

#include <SerialIO.h>

Functions

void setup()

void loop()

Variables

rc_channels_t channelData

sbus receiver & Serial

file sbus_basic.ino

#include <SerialIO.h>

Defines

SBUS_TX_PIN

SBUS_RX_PIN

Functions

void setup()

void loop()

Variables

rc_channels_t rcdata

sbus receiver & Serial1

file crsf.cpp: #include “crsf.h”

file crsf.h

#include “crsf_protocol.h”

#include “../SerialIO.h”

Header file for the CRSF protocol implementation.

Author: Witty-Wizard

Defines

CRSF_H

CRC8_POLY_D5

file crsf_protocol.h

#include <stdint.h>

Defines

CRSF_PROTOCOL_H

PACKED

CRSF_BAUDRATE: CRSF default baud rate.

CRSF_NUM_CHANNELS: CRSF number of channels.

CRSF_CHANNEL_VALUE_MIN: 987us - actual CRSF min is 0 with E.Limits on/*#end#*/

CRSF_CHANNEL_VALUE_1000

CRSF_CHANNEL_VALUE_MID

CRSF_CHANNEL_VALUE_2000

CRSF_CHANNEL_VALUE_MAX: 2012us - actual CRSF max is 1984 with E.Limits on/*#end#*/

CRSF_CHANNEL_VALUE_SPAN

CRSF_MAX_PACKET_SIZE: max declared len is 62+DEST+LEN on top of that = 64/*#end#*/

CRSF_MAX_PAYLOAD_LEN: Max size of payload in [dest] [len] [type] [payload] [crc8]/*#end#*/.

Typedefs

typedef struct crsf_header_s crsf_header_t: Heder of CRSF Packet

typedef struct crsf_channels_s crsf_channels_t: RC Packet Frame

typedef struct crsfPayloadLinkstatistics_s crsfLinkStatistics_t: Payload Statics

typedef struct crsf_sensor_battery_s crsf_sensor_battery_t: Battery Voltage parameters

typedef struct crsf_sensor_gps_s crsf_sensor_gps_t: GPS parameters

Enums

Length of different CRSF frame

Values:

enumerator CRSF_FRAME_LENGTH_ADDRESS

enumerator CRSF_FRAME_LENGTH_FRAMELENGTH

enumerator CRSF_FRAME_LENGTH_TYPE

enumerator CRSF_FRAME_LENGTH_CRC

enumerator CRSF_FRAME_LENGTH_TYPE_CRC

enumerator CRSF_FRAME_LENGTH_EXT_TYPE_CRC

enumerator CRSF_FRAME_LENGTH_NON_PAYLOAD

Length of CRSF frames

Values:

enumerator CRSF_FRAME_GPS_PAYLOAD_SIZE

enumerator CRSF_FRAME_BATTERY_SENSOR_PAYLOAD_SIZE

enumerator CRSF_FRAME_LINK_STATISTICS_PAYLOAD_SIZE

enumerator CRSF_FRAME_RC_CHANNELS_PAYLOAD_SIZE

enumerator CRSF_FRAME_ATTITUDE_PAYLOAD_SIZE

enum crsf_frame_type_e

CRSF Sensor frame type

Values:

enumerator CRSF_FRAMETYPE_GPS

enumerator CRSF_FRAMETYPE_BATTERY_SENSOR

enumerator CRSF_FRAMETYPE_LINK_STATISTICS

enumerator CRSF_FRAMETYPE_OPENTX_SYNC

enumerator CRSF_FRAMETYPE_RADIO_ID

enumerator CRSF_FRAMETYPE_RC_CHANNELS_PACKED

enumerator CRSF_FRAMETYPE_ATTITUDE

enumerator CRSF_FRAMETYPE_FLIGHT_MODE

enumerator CRSF_FRAMETYPE_DEVICE_PING

enumerator CRSF_FRAMETYPE_DEVICE_INFO

enumerator CRSF_FRAMETYPE_PARAMETER_SETTINGS_ENTRY

enumerator CRSF_FRAMETYPE_PARAMETER_READ

enumerator CRSF_FRAMETYPE_PARAMETER_WRITE

enumerator CRSF_FRAMETYPE_COMMAND

enumerator CRSF_FRAMETYPE_MSP_REQ

enumerator CRSF_FRAMETYPE_MSP_RESP

enumerator CRSF_FRAMETYPE_MSP_WRITE

enum crsf_addr_e

CRSF sensor address

Values:

enumerator CRSF_ADDRESS_BROADCAST

enumerator CRSF_ADDRESS_USB

enumerator CRSF_ADDRESS_TBS_CORE_PNP_PRO

enumerator CRSF_ADDRESS_RESERVED1

enumerator CRSF_ADDRESS_CURRENT_SENSOR

enumerator CRSF_ADDRESS_GPS

enumerator CRSF_ADDRESS_TBS_BLACKBOX

enumerator CRSF_ADDRESS_FLIGHT_CONTROLLER

enumerator CRSF_ADDRESS_RESERVED2

enumerator CRSF_ADDRESS_RACE_TAG

enumerator CRSF_ADDRESS_RADIO_TRANSMITTER

enumerator CRSF_ADDRESS_CRSF_RECEIVER

enumerator CRSF_ADDRESS_CRSF_TRANSMITTER

Functions

static inline uint16_t htobe16(uint16_t val)

static inline uint16_t be16toh(uint16_t val)

static inline uint32_t htobe32(uint32_t val)

static inline uint32_t be32toh(uint32_t val)

file fport.cpp

#include “fport.h”

Source file for the F.Port implementations.

Author: Witty-Wizard

file fport.h

#include “../SerialIO.h”

#include “fport_protocol.h”

Header file for the FPort Protocol definations.

Author: Witty-Wizard

Defines

FPORT_H

file fport_protocol.h

#include <stdint.h>

Header file for the F.Port protocol implementation.

Defines

FPORT_PROTOCOL_H

PACKED

FPORT_BAUDRATE: F.Port baudrate.

FPORT_MAX_PACKET_SIZE: F.Port maximum packet length.

FPORT_END_BYTES

Typedefs

typedef struct fport_channels_s fport_channels_t

Enums

enum fport_frame_type_e

Values:

enumerator FPORT_FRAMETYPE_RC_CHANNELS_PACKED

enumerator FPORT_FRAMETYPE_DOWNLINK

enumerator FPORT_FRAMETYPE_UPLINK

file ibus.cpp: #include “ibus.h”

file ibus.h

#include “../SerialIO.h”

#include “ibus_protocol.h”

Header file for the Ibus protocol implementation.

Defines

IBUS_H

file ibus_protocol.h

#include <stdint.h>

Header file for the iBus protocol implementation.

Defines

IBUS_PROTOCOL_H

PACKED

IBUS_MAX_PACKET_SIZE: Maximum packet size for the IBUS protocol.

IBUS_BAUDRATE: Baud rate for IBUS communication.

IBUS_HEADER1

IBUS_HEADER2

Typedefs

typedef struct ibus_channels_s ibus_channels_t

file sbus.cpp

#include “sbus.h”

Source file for the SBus implementations.

Author: Witty-Wizard

file sbus.h

#include “../SerialIO.h”

#include “sbus_protocol.h”

Header file for the SBUS protocol implementation.

Defines

SBUS_H

file sbus_protocol.h

#include <stdint.h>

Header file for the SBus protocol implementation.

Defines

SBUS_PROTOCOL_H

PACKED

HEADER_SBUS: SBus Header Byte.

FOOTER_SBUS: SBus Footer Byte.

SBUS_BAUDRATE: SBus baudrate.

SBUS_MAX_PACKET_SIZE: SBus packet length.

SBUS_TIMEOUT: SBus timeout in milliseconds.

Typedefs

typedef struct sbus_channels_s sbus_channels_t

file SerialIO.cpp: #include “SerialIO.h”

file SerialIO.h

#include <Arduino.h>

#include <ibus/ibus_protocol.h>

#include “crsf/crsf.h”

#include “fport/fport.h”

#include “ibus/ibus.h”

#include “sbus/sbus.h”

Header file for SerialIO class, providing serial input/output (IO) functionality.

Author: WittyWizard

Defines

SerialIO_H

PACKED

Typedefs

typedef struct rc_channels_s rc_channels_t: Structure representing 16 RC channels using 11-bit values.

dir examples/atmel

dir src/crsf

dir examples/atmel/crsf_basic

dir examples/rp2040/crsf_basic

dir examples

dir src/fport

dir src/ibus

dir examples/atmel/ibus_basic

dir examples/rp2040/ibus_basic

dir examples/rp2040

dir src/sbus

dir examples/atmel/sbus_basic

dir examples/rp2040/sbus_basic

dir src