redux::sensors::canandmag::Canandmag Class Reference

#include <Canandmag.h>

Inheritance diagram for redux::sensors::canandmag::Canandmag:

Public Member Functions
	Canandmag (int canID)
units::turn_t	GetPosition ()
units::turn_t	GetAbsPosition ()
bool	SetPosition (units::turn_t newPosition, units::second_t timeout=20_ms)
bool	SetAbsPosition (units::turn_t newPosition, units::second_t timeout=20_ms, bool ephemeral=false)
bool	ZeroAll (units::second_t timeout=20_ms)
units::turns_per_second_t	GetVelocity ()
bool	MagnetInRange ()
CanandmagFaults	GetStickyFaults ()
CanandmagFaults	GetActiveFaults ()
units::celsius_t	GetTemperature ()
CanandmagStatus	GetStatus ()
void	ClearStickyFaults ()
void	SetPartyMode (uint8_t level)
Public Member Functions inherited from redux::canand::CanandDevice
virtual void	HandleMessage (CanandMessage &msg)=0
virtual CanandAddress &	GetAddress ()=0
bool	IsConnected (units::second_t timeout=2_s)
virtual std::string	GetDeviceClassName ()
std::string	GetDeviceName ()
virtual void	PreHandleMessage (CanandMessage &msg)
virtual void	CheckReceivedFirmwareVersion ()
virtual CanandFirmwareVersion	GetMinimumFirmwareVersion ()
bool	SendCANMessage (uint8_t apiIndex, uint8_t *data, uint8_t length)
template<std::size_t len> requires (len < 8U)
void	SendCANMessage (uint8_t msgId, std::span< std::byte, len > data)

Detailed Description

Class for the CAN interface of the Canandmag.

If you are using a Canandmag with Spark Max or Talon with the PWM output, see our Spark Max docs or our Talon SRX docs for information on how to use the encoder with the Rev and CTRE APIs.

The C++ vendordep uses the units library for all dimensioned values, including settings.

Operations that receive data from the device (position, velocity, faults, temperature) generally do not block. The object receives data asynchronously from the CAN packet receive thread and reads thus return the last data received.

Operations that set settings or change offsets will generally wait for up to 20ms by default as they will usually wait for a confirmation packet to be received in response – unless the blocking timeout is set to zero, in which case the operation swill not block.

Example code:

Canandmag canandmag{0}; // instantiates with encoder id 0 
 
// Reading the Canandmag
canandmag.GetPosition(); // returns a multi-turn relative position, in rotations (turns)
canandmag.GetAbsPosition(); // returns an absolute position bounded from [0..1) over one rotation
canandmag.GetVelocity(); // returns measured velocity in rotations per second
 
// Updating position
canandmag.SetPosition(-3.5_tr); // sets the relative position to -3.5 turns (does not persist on reboot)
canandmag.SetAbsPosition(330_deg, 0_s); // sets the absolute position to 330 degrees without blocking for confirmation (persists on reboot)
canandmag.ZeroAll(); // sets both the relative and absolute position to zero
 
// Changing configuration
CanandmagSettings settings;
settings.SetVelocityFilterWidth(25_ms); // sets the velocity filter averaging period to 25 ms
settings.SetInvertDirection(true); // make positive be clockwise instead of ccw opposite the sensor face
canandmag.SetSettings(settings, 20_ms); // apply the new settings to the device, with maximum 20 ms timeout per settings operation
 
// Faults
canandmag.ClearStickyFaults(); // clears all sticky faults (including the power cycle flag). This call does not block.
 
// this flag will always be true on boot until the sticky faults have been cleared, 
// so if this prints true the encoder has rebooted sometime between ClearStickyFaults and now.
CanandmagFaults faults = canandmag.GetStickyFaults(); // fetches faults
fmt::print("Encoder rebooted: {}\n", faults.powerCycle);
 
// Timestamped data
redux::frames::FrameData<units::turn_t> posFrameData = canandmag.GetPositionFrame().GetFrameData(); // gets current position + timestamp together
posFrameData.GetValue(); // fetched position in rotations
posFrameData.GetTimestamp(); // timestamp of the previous position

Constructor & Destructor Documentation

Canandmag()

redux::sensors::canandmag::Canandmag::Canandmag

(

int

canID

)

Constructor with the device's id. This object will be constant with respect to whatever CAN id assigned to it, so if a device changes id it may change which device this object reads from.

Parameters

canID

the device id to use

Member Function Documentation

ClearStickyFaults()

void redux::sensors::canandmag::Canandmag::ClearStickyFaults

(

)

Clears sticky faults.

It is recommended to clear this during initialization, so one can check if the encoder loses power during operation later.

This call does not block, so it may take up to the next status frame (default every 1000 ms) for the sticky faults to be updated.

GetAbsPosition()

units::turn_t redux::sensors::canandmag::Canandmag::GetAbsPosition

(

)

Gets the current absolute position of the encoder, in a scaled value from 0 inclusive to 1 exclusive. By default, higher values are in the counter-clockwise direction from the sensor face.

This value will persist across encoder power cycles making it appropriate for swerves/arms/etc.

Returns

absolute position in fraction of a rotation [0..1)

GetActiveFaults()

CanandmagFaults redux::sensors::canandmag::Canandmag::GetActiveFaults

(

)

Fetches active faults. Active faults are only active for as long as the error state exists.

Returns

CanandmagFaults of the active faults

GetPosition()

units::turn_t redux::sensors::canandmag::Canandmag::GetPosition

(

)

Gets the current integrated position in rotations.

This value does not wrap around, so turning a sensed axle multiple rotations will return multiple sensed rotations of position. By default, positive is in the counter-clockwise direction from the sensor face.

On encoder power-on, unlike the absolute value, this value will always initialize to zero.

Returns

signed relative position in rotations (range [-131072.0..131071.999938396484])

GetStatus()

CanandmagStatus redux::sensors::canandmag::Canandmag::GetStatus ( )

inline

Get the contents of the previous status packet, which includes active faults, sticky faults, and temperature.

Returns

device status as a status struct

GetStickyFaults()

CanandmagFaults redux::sensors::canandmag::Canandmag::GetStickyFaults

(

)

Fetches sticky faults. Sticky faults are the active faults, except once set they do not become unset until ClearStickyFaults() is called.

Returns

CanandmagFaults of the sticky faults

GetTemperature()

units::celsius_t redux::sensors::canandmag::Canandmag::GetTemperature

(

)

Get onboard encoder temperature readings in degrees Celsius.

Returns

temperature in degrees Celsius

GetVelocity()

units::turns_per_second_t redux::sensors::canandmag::Canandmag::GetVelocity

(

)

Returns the measured velocity in rotations per second.

Returns

velocity, in rotations (turns) per second

MagnetInRange()

bool redux::sensors::canandmag::Canandmag::MagnetInRange

(

)

Returns whether the encoder magnet is in range of the sensor or not. This can be seen visually on the sensor – a green LED is in range, whereas a red LED is out of range.

Returns

whether the output shaft magnet is in range.

SetAbsPosition()

bool redux::sensors::canandmag::Canandmag::SetAbsPosition	(	units::turn_t	newPosition,
		units::second_t	timeout = 20_ms,
		bool	ephemeral = false
	)

Sets the new absolute position value for the encoder which will (by default) persist across reboots.

Parameters

newPosition	new absolute position in fraction of a rotation (acceptable range [0..1))
timeout	maximum time to wait for the operation to be confirmed (default 0.020 seconds). Set to 0 to not check (and not block).
ephemeral	if true, set the setting ephemerally – the new zero offset will not persist on power cycle.

Returns

true on success, false on timeout

SetPartyMode()

void redux::sensors::canandmag::Canandmag::SetPartyMode

(

uint8_t

level

)

Controls "party mode" – an encoder identification tool that blinks the onboard LED various colors at a user-specified strobe period. The strobe period of the LED will be (50 milliseconds * level). Setting this to 0 disables party mode.

This function does not block.

Parameters

level

the party level value to set.

SetPosition()

bool redux::sensors::canandmag::Canandmag::SetPosition	(	units::turn_t	newPosition,
		units::second_t	timeout = 20_ms
	)

Sets the new relative (multi-turn) position of the encoder to the given value.

Note that this does not update the absolute position, and this value is lost on a power cycle. To update the absolute position, use Canandmag::SetAbsPosition

Parameters

newPosition	new position in rotations
timeout	maximum time to wait for the operation to be confirmed (default 0.020 seconds). Set to 0 to not check (and not block).

Returns

true on success, false on timeout

ZeroAll()

bool redux::sensors::canandmag::Canandmag::ZeroAll

(

units::second_t

timeout = 20_ms

)

Sets both the current absolute and relative encoder position to 0 – generally equivalent to pressing the physical zeroing button on the encoder.

Parameters

timeout

maximum time in seconds to wait for each operation to be confirmed (there are 2 ops for zeroing both absolute and relative positions, so the wait is up to 2x timouet). Set to 0 to not check (and not block).

Returns

true on success, false on timeout

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The documentation for this class was generated from the following file:

• src/main/native/include/redux/sensors/Canandmag.h