-- GPIO pin services using a user LED at /dev/userled -- Copyright (C)2018-2023, Philip Munts dba Munts Technologies. -- -- Redistribution and use in source and binary forms, with or without -- modification, are permitted provided that the following conditions are met: -- -- * Redistributions of source code must retain the above copyright notice, -- this list of conditions and the following disclaimer. -- -- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" -- AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE -- IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE -- ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE -- LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR -- CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF -- SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS -- INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN -- CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) -- ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE -- POSSIBILITY OF SUCH DAMAGE. PACKAGE GPIO.UserLED IS -- Determine whether the user LED is available FUNCTION Available RETURN Boolean; -- Class definitions TYPE PinSubclass IS NEW GPIO.PinInterface WITH PRIVATE; Destroyed : CONSTANT PinSubclass; -- Constructor FUNCTION Create(state : Boolean := False) RETURN GPIO.Pin; -- Initializer PROCEDURE Initialize(Self : IN OUT PinSubclass; state : Boolean := False); -- Destroyer PROCEDURE Destroy(Self : IN OUT PinSubclass); -- Read GPIO pin state FUNCTION Get(Self : IN OUT PinSubclass) RETURN Boolean; -- Write GPIO pin state PROCEDURE Put(Self : IN OUT PinSubclass; state : Boolean); -- Retrieve the underlying Linux file descriptor FUNCTION fd(Self : PinSubclass) RETURN Integer; PRIVATE -- Check whether GPIO pin has been destroyed PROCEDURE CheckDestroyed(Self : PinSubclass); TYPE PinSubclass IS NEW GPIO.PinInterface WITH RECORD myfd : Integer := -1; END RECORD; Destroyed : CONSTANT PinSubclass := PinSubclass'(myfd => -1); END GPIO.UserLED;