redux::canand::utils Namespace Reference

Functions
constexpr uint8_t	getDeviceType (uint32_t fullId)
constexpr uint8_t	getApiPage (uint32_t fullId)
constexpr uint8_t	getApiIndex (uint32_t fullId)
constexpr uint8_t	getDeviceId (uint32_t fullId)
constexpr bool	idMatches (uint32_t idToCompare, uint8_t deviceType, uint8_t devId)
constexpr uint32_t	constructMessageId (uint8_t deviceType, uint16_t devId, uint8_t msgId)
constexpr std::chrono::duration< double, std::ratio< 1LL, 1LL > >	toChronoSeconds (units::second_t seconds)
constexpr void	memcpyLE (void *dst, void *src, size_t len)
constexpr uint8_t	extractU8 (uint64_t data, uint8_t width, uint8_t offset)
constexpr uint16_t	extractU16 (uint64_t data, uint8_t width, uint8_t offset)
constexpr uint32_t	extractU32 (uint64_t data, uint8_t width, uint8_t offset)
constexpr uint64_t	extractU64 (uint64_t data, uint8_t width, uint8_t offset)
constexpr int8_t	extractI8 (uint64_t data, uint8_t width, uint8_t offset)
constexpr int16_t	extractI16 (uint64_t data, uint8_t width, uint8_t offset)
constexpr int32_t	extractI32 (uint64_t data, uint8_t width, uint8_t offset)
constexpr int64_t	extractI64 (uint64_t data, uint8_t width, uint8_t offset)
constexpr float	extractF24 (uint64_t data, uint8_t offset)
constexpr float	extractF32 (uint64_t data, uint8_t offset)
constexpr double	extractF64 (uint64_t data)
constexpr bool	extractBool (uint64_t data, uint8_t offset)
constexpr uint64_t	packUInt (uint64_t data, uint8_t width, uint8_t offset)
constexpr uint64_t	packInt (int64_t data, uint8_t width, uint8_t offset)
constexpr uint64_t	packF24 (float data, uint8_t offset)
constexpr uint64_t	packF32 (float data, uint8_t offset)
constexpr uint64_t	packF64 (double data, uint8_t offset)
constexpr uint64_t	packBool (bool data, uint8_t offset)
template<typename E >
constexpr std::underlying_type< E >::type	to_underlying (E e) noexcept

Detailed Description

Series of utility functions for CAN messaging and bit manipulation.

For more information, see https://docs.wpilib.org/en/stable/docs/software/can-devices/can-addressing.html

Function Documentation

constructMessageId()

constexpr uint32_t redux::canand::utils::constructMessageId ( uint8_t  deviceType, uint16_t  devId, uint8_t  msgId  )

constexpr

Construct a CAN message id to send to a Redux device.

Parameters

deviceType	the device id code
devId	CAN device id
msgId	API message id

Returns

a 29-bit full CAN message id

extractBool()

constexpr bool redux::canand::utils::extractBool ( uint64_t  data, uint8_t  offset  )

constexpr

Extracts a boolean from a bitfield.

Parameters

data	bitfield to extract from
offset	the offset of the boolean bit in the bitfield

Returns

extracted boolean value.

extractF24()

constexpr float redux::canand::utils::extractF24 ( uint64_t  data, uint8_t  offset  )

constexpr

Extracts a 24-bit float.

24-bit floats have 1 sign bit, 8 exponent bits, and 15 mantissa bits.

Parameters

data	bitfield to extract from
offset	bit offset of the float to extract

Returns

extracted float

extractF32()

constexpr float redux::canand::utils::extractF32 ( uint64_t  data, uint8_t  offset  )

constexpr

Extracts a 32-bit single-precision float.

Parameters

data	bitfield to extract from
offset	bit offset of the float to extract

Returns

extracted float

extractF64()

constexpr double redux::canand::utils::extractF64 ( uint64_t  data )

constexpr

Extracts a 64-bit double-precision float.

Parameters

data	bitfield to extract from

Returns

extracted float

extractI16()

constexpr int16_t redux::canand::utils::extractI16 ( uint64_t  data, uint8_t  width, uint8_t  offset  )

constexpr

Extracts a signed integer up to 16 bits wide, performing a sign extension if necessary.

Parameters

data	bitfield to extract from
width	width of integer in bits. Values larger than 16 are undefined behavior.
offset	bit offset of the integer to extract

Returns

extracted integer

extractI32()

constexpr int32_t redux::canand::utils::extractI32 ( uint64_t  data, uint8_t  width, uint8_t  offset  )

constexpr

Extracts a signed integer up to 32 bits wide, performing a sign extension if necessary.

Parameters

data	bitfield to extract from
width	width of integer in bits. Values larger than 32 are undefined behavior.
offset	bit offset of the integer to extract

Returns

extracted integer

extractI64()

constexpr int64_t redux::canand::utils::extractI64 ( uint64_t  data, uint8_t  width, uint8_t  offset  )

constexpr

Extracts a signed integer up to 64 bits wide, performing a sign extension if necessary.

Parameters

data	bitfield to extract from
width	width of integer in bits. Values larger than 64 are undefined behavior.
offset	bit offset of the integer to extract

Returns

extracted integer

extractI8()

constexpr int8_t redux::canand::utils::extractI8 ( uint64_t  data, uint8_t  width, uint8_t  offset  )

constexpr

Extracts a signed integer up to 8 bits wide, performing a sign extension if necessary.

Parameters

data	bitfield to extract from
width	width of integer in bits. Values larger than 8 are undefined behavior.
offset	bit offset of the integer to extract

Returns

extracted integer

extractU16()

constexpr uint16_t redux::canand::utils::extractU16 ( uint64_t  data, uint8_t  width, uint8_t  offset  )

constexpr

Extracts an unsigned integer up to 16 bits wide.

Parameters

data	bitfield to extract from
width	width of integer in bits. Values larger than 16 are undefined behavior.
offset	bit offset of the integer to extract

Returns

extracted integer

extractU32()

constexpr uint32_t redux::canand::utils::extractU32 ( uint64_t  data, uint8_t  width, uint8_t  offset  )

constexpr

Extracts an unsigned integer up to 32 bits wide.

Parameters

data	bitfield to extract from
width	width of integer in bits. Values larger than 32 are undefined behavior.
offset	bit offset of the integer to extract

Returns

extracted integer

extractU64()

constexpr uint64_t redux::canand::utils::extractU64 ( uint64_t  data, uint8_t  width, uint8_t  offset  )

constexpr

Extracts an unsigned integer up to 64 bits wide.

Parameters

data	bitfield to extract from
width	width of integer in bits. Values larger than 64 are undefined behavior.
offset	bit offset of the integer to extract

Returns

extracted integer

extractU8()

constexpr uint8_t redux::canand::utils::extractU8 ( uint64_t  data, uint8_t  width, uint8_t  offset  )

constexpr

Extracts an unsigned integer up to 8 bits wide.

Parameters

data	bitfield to extract from
width	width of integer in bits. Values larger than 8 are undefined behavior.
offset	bit offset of the integer to extract

Returns

extracted integer

getApiIndex()

constexpr uint8_t redux::canand::utils::getApiIndex ( uint32_t  fullId )

constexpr

Extracts the 8-bit API index from a full message id. Instead of doing a 6bit/4bit split for api class/api index, we use 2bit/8bit.

Parameters

fullId

the full 29-bit message id

Returns

the product id code

getApiPage()

constexpr uint8_t redux::canand::utils::getApiPage ( uint32_t  fullId )

constexpr

Extracts 2-bit product id/API class from a full message id. Instead of doing a 6bit/4bit split for api class/api index, we use 2bit/8bit.

Parameters

fullId

the full 29-bit message id

Returns

the product id code

getDeviceId()

constexpr uint8_t redux::canand::utils::getDeviceId ( uint32_t  fullId )

constexpr

Extracts 6-bit device id from a full message id This is the "CAN id" that end users will see and care about.

Parameters

fullId

the full 29-bit message id

Returns

the device CAN id

getDeviceType()

constexpr uint8_t redux::canand::utils::getDeviceType ( uint32_t  fullId )

constexpr

Extracts 5-bit device type code from a full message id

Parameters

fullId

the full 29-bit message id

Returns

the device type code

idMatches()

constexpr bool redux::canand::utils::idMatches ( uint32_t  idToCompare, uint8_t  deviceType, uint8_t  devId  )

constexpr

Checks if a full CAN id will match against device type, product id, and device id We use this to determine if a message is intended for a specific device.

Parameters

idToCompare	full 29-bit id
deviceType	device id code
devId	device id

Returns

whether the parameters matches the message id

memcpyLE()

constexpr void redux::canand::utils::memcpyLE ( void *  dst, void *  src, size_t  len  )

constexpr

Converts a byte buffer to a little endian buffer.

Parameters

dst	destination ptr
src	source ptr
len	the length of the data in bytes. If less than 8, the unused bit-space will be zeros.

packBool()

constexpr uint64_t redux::canand::utils::packBool ( bool  data, uint8_t  offset  )

constexpr

Packs a boolean as a single bit into a 64-bit field.

Parameters

data	the boolean value
offset	the 0-indexed offset of the bit in the bitfield

Returns

packed bitfield that can be ORed with other fields to construct a full bitfield

packF24()

constexpr uint64_t redux::canand::utils::packF24 ( float  data, uint8_t  offset  )

constexpr

Packs a float into a 24-bit field. This is accomplished by ignoring the least significant 8 bits of the mantissa.

Parameters

data	the float to pack
offset	the 0-indexed offset of the float in the bitfield

Returns

packed bitfield that can be ORed with other fields to construct a full bitfield

packF32()

constexpr uint64_t redux::canand::utils::packF32 ( float  data, uint8_t  offset  )

constexpr

Packs a float into a 32-bit field.

Parameters

data	the float to pack
offset	the 0-indexed offset of the float in the bitfield

Returns

packed bitfield that can be ORed with other fields to construct a full bitfield

packF64()

constexpr uint64_t redux::canand::utils::packF64 ( double  data, uint8_t  offset  )

constexpr

Packs a double into a 64-bit field.

Parameters

data	the double to pack
offset	the 0-indexed offset of the double in the bitfield

Returns

packed bitfield that can be ORed with other fields to construct a full bitfield

packInt()

constexpr uint64_t redux::canand::utils::packInt ( int64_t  data, uint8_t  width, uint8_t  offset  )

constexpr

Packs a signed integer of variable length into a bitfield as twos complement.

Parameters

data	the signed integer to pack
width	the width of the signed integer
offset	the 0-indexed offset of the integer in the bitfield

Returns

packed bitfield that can be ORed with other fields to construct a full bitfield

packUInt()

constexpr uint64_t redux::canand::utils::packUInt ( uint64_t  data, uint8_t  width, uint8_t  offset  )

constexpr

Packs an unsigned integer of variable length into a bitfield.

Parameters

data	the unsigned integer to pack
width	the width of the unsigned integer
offset	the 0-indexed offset of the integer in the bitfield

Returns

packed bitfield that can be ORed with other fields to construct a full bitfield

to_underlying()

template<typename E >

constexpr std::underlying_type< E >::type redux::canand::utils::to_underlying ( E  e )

constexprnoexcept

Converts an enum to an underlying type

Parameters

e	value to convert

Returns

underlying type

toChronoSeconds()

constexpr std::chrono::duration< double, std::ratio< 1LL, 1LL > > redux::canand::utils::toChronoSeconds ( units::second_t  seconds )

constexpr

Converts seconds from the units library to seconds in std::chrono::duration.

Useful for condition variables.

Parameters

seconds

in units::second_t terms

Returns

seconds in std::chrono::duration terms