Flipper Expansion Protocol parser reference implementation. More...

#include <stddef.h>
#include <stdint.h>
#include <stdbool.h>

Data Structures
struct	ExpansionFrameHeader
	Frame header structure. More...

struct	ExpansionFrameHeartbeat
	Heartbeat frame contents. More...

struct	ExpansionFrameStatus
	Status frame contents. More...

struct	ExpansionFrameBaudRate
	Baud rate frame contents. More...

struct	ExpansionFrameControl
	Control frame contents. More...

struct	ExpansionFrameData
	Data frame contents. More...

struct	ExpansionFrame
	Expansion protocol frame structure. More...

Macros
#define	EXPANSION_PROTOCOL_DEFAULT_BAUD_RATE (9600UL)
	Default baud rate to start all communications at.

#define	EXPANSION_PROTOCOL_MAX_DATA_SIZE (64U)
	Maximum data size per frame, in bytes.

#define	EXPANSION_PROTOCOL_TIMEOUT_MS (250U)
	Maximum allowed inactivity period, in milliseconds.

#define	EXPANSION_PROTOCOL_BAUD_CHANGE_DT_MS (25U)
	Dead time after changing connection baud rate.

Typedefs
typedef uint8_t	ExpansionFrameChecksum
	Expansion checksum type.

typedef size_t(*	ExpansionFrameReceiveCallback) (uint8_t data, size_t data_size, void context)
	Receive function type declaration.

typedef size_t(*	ExpansionFrameSendCallback) (const uint8_t data, size_t data_size, void context)
	Send function type declaration.

Enumerations
enum	ExpansionFrameType { ExpansionFrameTypeHeartbeat = 1 , ExpansionFrameTypeStatus = 2 , ExpansionFrameTypeBaudRate = 3 , ExpansionFrameTypeControl = 4 , ExpansionFrameTypeData = 5 , ExpansionFrameTypeReserved }
	Enumeration of supported frame types. More...

enum	ExpansionFrameError { ExpansionFrameErrorNone = 0x00 , ExpansionFrameErrorUnknown = 0x01 , ExpansionFrameErrorBaudRate = 0x02 }
	Enumeration of possible error types. More...

enum	ExpansionFrameControlCommand { ExpansionFrameControlCommandStartRpc = 0x00 , ExpansionFrameControlCommandStopRpc = 0x01 , ExpansionFrameControlCommandEnableOtg = 0x02 , ExpansionFrameControlCommandDisableOtg = 0x03 }
	Enumeration of suported control commands. More...

enum	ExpansionProtocolStatus { ExpansionProtocolStatusOk , ExpansionProtocolStatusErrorFormat , ExpansionProtocolStatusErrorChecksum , ExpansionProtocolStatusErrorCommunication }
	Enumeration of protocol parser statuses. More...

Detailed Description

Flipper Expansion Protocol parser reference implementation.

This file is licensed separately under The Unlicense. See https://unlicense.org/ for more details.

This parser is written with low-spec hardware in mind. It does not use dynamic memory allocation or Flipper-specific libraries and can be included directly into any module's firmware's sources.

Typedef Documentation

◆ ExpansionFrameReceiveCallback

typedef size_t(* ExpansionFrameReceiveCallback) (uint8_t *data, size_t data_size, void *context)

Receive function type declaration.

See also: expansion_frame_decode().

Parameters

[out]	data	pointer to the buffer to reveive the data into.
[in]	data_size	maximum output buffer capacity, in bytes.
[in,out]	context	pointer to a user-defined context object.

Returns: number of bytes written into the output buffer.

◆ ExpansionFrameSendCallback

typedef size_t(* ExpansionFrameSendCallback) (const uint8_t *data, size_t data_size, void *context)

Send function type declaration.

See also: expansion_frame_encode().

Parameters

[in]	data	pointer to the buffer containing the data to be sent.
[in]	data_size	size of the data to send, in bytes.
[in,out]	context	pointer to a user-defined context object.

Returns: number of bytes actually sent.

Enumeration Type Documentation

◆ ExpansionFrameControlCommand

enum ExpansionFrameControlCommand

Enumeration of suported control commands.

Enumerator
ExpansionFrameControlCommandStartRpc	Start an RPC session. Must only be used while the RPC session is NOT active.
ExpansionFrameControlCommandStopRpc	Stop an open RPC session. Must only be used while the RPC session IS active.
ExpansionFrameControlCommandEnableOtg	Enable OTG (5V) on external GPIO. Must only be used while the RPC session is NOT active, otherwise OTG is to be controlled via RPC messages.
ExpansionFrameControlCommandDisableOtg	Disable OTG (5V) on external GPIO. Must only be used while the RPC session is NOT active, otherwise OTG is to be controlled via RPC messages.

◆ ExpansionFrameError

enum ExpansionFrameError

Enumeration of possible error types.

Enumerator
ExpansionFrameErrorNone	No error occurred.
ExpansionFrameErrorUnknown	An unknown error has occurred (generic response).
ExpansionFrameErrorBaudRate	Requested baud rate is not supported.

◆ ExpansionFrameType

enum ExpansionFrameType

Enumeration of supported frame types.

Enumerator
ExpansionFrameTypeHeartbeat	Heartbeat frame.
ExpansionFrameTypeStatus	Status report frame.
ExpansionFrameTypeBaudRate	Baud rate negotiation frame.
ExpansionFrameTypeControl	Control frame.
ExpansionFrameTypeData	Data frame.
ExpansionFrameTypeReserved	Special value.

◆ ExpansionProtocolStatus

enum ExpansionProtocolStatus

Enumeration of protocol parser statuses.

Enumerator
ExpansionProtocolStatusOk	No error has occurred.
ExpansionProtocolStatusErrorFormat	Invalid frame type.
ExpansionProtocolStatusErrorChecksum	Checksum mismatch.
ExpansionProtocolStatusErrorCommunication	Input/output error.

Data Structures

Macros

Typedefs

Enumerations