private void Pin_ValueChanged(GpioPin sender, GpioPinValueChangedEventArgs args)
{
lock (_lock)
{
if (!_evaluatingRows)
{
IGpioPinMapping mapping = this.PinMappings.Where(t => t.PinNumber == sender.PinNumber).SingleOrDefault();
if (mapping != null)
{
PinChangedStatus status = mapping.GetChangedStatus(args.Edge);
if (status != PinChangedStatus.None)
{
this.OnPinValueChanged(mapping, status);
}
}
}
}
}
public PinChangedStatus GetChangedStatus(GpioPinEdge edge)
{
PinChangedStatus returnValue = PinChangedStatus.None;
GpioPinValue currentValue = this.GpioPin.Read();
try
{
if (edge == GpioPinEdge.RisingEdge && this.PreviousValue == GpioPinValue.Low && currentValue != this.PreviousValue)
{
returnValue = PinChangedStatus.WentHigh;
}
else if (edge == GpioPinEdge.FallingEdge && this.PreviousValue == GpioPinValue.High && currentValue != this.PreviousValue)
{
returnValue = PinChangedStatus.WentLow;
}
}
finally
{
this.PreviousValue = currentValue;
}
return(returnValue);
}
protected virtual void OnPinValueChanged(IGpioPinMapping mapping, PinChangedStatus status)
{
try
{
// ***
// *** Need to ignore other keypad changes until this is complete
// ***
_evaluatingRows = true;
if (status == PinChangedStatus.WentHigh)
{
// ***
// *** Once the column and row is known we can determine the key
// ***
ICharacterGridMapping characterGridMapping = null;
// ***
// *** Need to change each row to LOW until the pin we have changes again. This helps determine which
// *** row is selected.
// ***
foreach (var rowMapping in this.RowMappings)
{
try
{
rowMapping.GpioPin.Write(GpioPinValue.Low);
GpioPinValue newValue = mapping.GpioPin.Read();
if (newValue == GpioPinValue.Low)
{
// ***
// *** Select the character mapping
// ***
characterGridMapping = this.CharacterGridMappings.Where(t => t.Row == rowMapping.MatrixValue && t.Column == mapping.MatrixValue).SingleOrDefault();
if (characterGridMapping != null)
{
if (this.EnableButtonUpEvent)
{
_lastCharacterDown = characterGridMapping;
}
break;
}
}
}
finally
{
// ***
// *** Need the pin to be on high in it's default state
// ***
rowMapping.GpioPin.Write(GpioPinValue.High);
}
}
if (characterGridMapping != null)
{
this.OnKeyEvent(new KeyPadEventArgs(characterGridMapping.Value, KeyDownEventType.ButtonDown));
}
}
else
{
if (_lastCharacterDown != null)
{
char key = _lastCharacterDown.Value;
_lastCharacterDown = null;
this.OnKeyEvent(new KeyPadEventArgs(key, KeyDownEventType.ButtonUp));
}
}
}
finally
{
_evaluatingRows = false;
}
}
protected virtual void OnPinValueChanged(IGpioPinMapping mapping, PinChangedStatus status)
{
try
{
// ***
// *** Need to ignore other keypad changes until this is complete
// ***
_evaluatingRows = true;
if (status == PinChangedStatus.WentHigh)
{
// ***
// *** Once the column and row is known we can determine the key
// ***
ICharacterGridMapping characterGridMapping = null;
// ***
// *** Need to change each row to LOW until the pin we have changes again. This helps determine which
// *** row is selected.
// ***
foreach (var rowMapping in this.RowMappings)
{
try
{
rowMapping.GpioPin.Write(GpioPinValue.Low);
GpioPinValue newValue = mapping.GpioPin.Read();
if (newValue == GpioPinValue.Low)
{
// ***
// *** Select the character mapping
// ***
characterGridMapping = this.CharacterGridMappings.Where(t => t.Row == rowMapping.MatrixValue && t.Column == mapping.MatrixValue).SingleOrDefault();
if (characterGridMapping != null)
{
if (this.EnableButtonUpEvent) { _lastCharacterDown = characterGridMapping; }
break;
}
}
}
finally
{
// ***
// *** Need the pin to be on high in it's default state
// ***
rowMapping.GpioPin.Write(GpioPinValue.High);
}
}
if (characterGridMapping != null)
{
this.OnKeyEvent(new KeyPadEventArgs(characterGridMapping.Value, KeyDownEventType.ButtonDown));
}
}
else
{
if (_lastCharacterDown != null)
{
char key = _lastCharacterDown.Value;
_lastCharacterDown = null;
this.OnKeyEvent(new KeyPadEventArgs(key, KeyDownEventType.ButtonUp));
}
}
}
finally
{
_evaluatingRows = false;
}
}
