// MCP23017 I2C GPIO Expander Services.
// Copyright (C)2020-2023, 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.
namespace IO.Devices.MCP23017.GPIO
{
///
/// Encapsulates MCP23017 GPIO pins.
///
public class Pin : IO.Interfaces.GPIO.Pin
{
private readonly IO.Devices.MCP23017.Device dev;
private readonly uint mask;
///
/// Create a single MCP23017 GPIO pin.
///
/// MCP23017 device object.
/// MCP23017 I/O channel number.
/// GPIO pin data direction.
/// Initial GPIO output state.
public Pin(IO.Devices.MCP23017.Device dev, int channel,
IO.Interfaces.GPIO.Direction dir, bool state = false)
{
// Validate parameters
if ((channel < IO.Devices.MCP23017.Device.MinChannel) ||
(channel > IO.Devices.MCP23017.Device.MaxChannel))
throw new System.Exception("Invalid channel number.");
mask = (uint)(1 << channel);
if (dir == IO.Interfaces.GPIO.Direction.Output)
dev.Direction |= mask;
else
dev.Direction &= ~mask;
this.dev = dev;
this.state = state;
}
///
/// Read/Write GPIO state property.
///
public bool state
{
get
{
return (dev.Port & mask) != 0;
}
set
{
if (value)
dev.Port |= mask;
else
dev.Port &= ~mask;
}
}
}
}