Output Pin#

Hardware Interface#

Defined in namespace hal

#include <libhal/output_pin.hpp>

class output_pin#

Digital output pin hardware abstraction.

Use this to drive a pin HIGH or LOW in order to send a control signal or turn off or on an LED.

Implementations of this interface can be backed by external devices such as I/O expanders or other micro-controllers.

Public Functions

inline status configure(const settings &p_settings)#

Configure the output pin to match the settings supplied.

Parameters:: p_settings – - settings to apply to output pin
Throws:: std::errc::invalid_argument – if the settings could not be achieved.
Returns:: status - success or failure

inline result<set_level_t> level(bool p_high)#

Set the state of the pin.

Parameters:: p_high – - if true then the pin state is set to HIGH voltage. If false, the pin state is set to LOW voltage.
Returns:: result<set_level_t> - success or failure

inline result<level_t> level()#

Read the current state of the output pin.

Implementations must read the pin state from hardware and will not simply cache the results from the execution of level(bool).

This pin may not equal the state set by level(bool) when the pin is configured as open-drain.

Returns:: result<level_t> - return the current level state of the output pin

struct level_t#

Pin level reading structure.

Public Members

struct set_level_t#

Feedback from setting the pin state.

This structure is currently empty as no feedback has been determined for now. This structure may be expanded in the future.

struct settings#

Generic settings for output pins.

Public Members

pin_resistor resistor = pin_resistor::none #: Pull resistor for the pin. This generally only helpful when open drain is enabled.

bool open_drain = false#: Starting level of the output pin. HIGH voltage defined as true and LOW voltage defined as false.

Defined in namespace hal

#include <libhal-util/output_pin.hpp>

group OutputPin

Functions

constexpr auto operator==(const output_pin::settings &p_lhs, const output_pin::settings &p_rhs)#

Compares two output pin states, compares both resistor and open drain.

Parameters:

Returns:

A boolean if they are the same or not.