internal GpioPort DeviceGet(Cpu.Pin pin, bool writeTraceOnError)
{
// If pin as index is out of range of the _ports array, then we return GpioPortNull for that index
// In particular it happens for GPOI_PORT_NONE ( -1 )
if ((int)pin < 0 || (int)pin >= _ports.Length)
{
return(new GpioPortNull(pin, GpioPortMode.None));
}
GpioPort port = _ports[(int)pin];
if (port == null)
{
port = new GpioPortNull(pin);
_ports[(int)pin] = port;
}
if (writeTraceOnError && port is GpioPortNull)
{
GpioPortNull nullPort = (GpioPortNull)port;
if (nullPort.DisplayWarning || Emulator.Verbose)
{
Trace.WriteLine("Warning: System attempts to access a GPIO port at pin " + pin + " that was not configured.");
nullPort.TurnOffWarning();
}
}
return(port);
}
internal override void UnregisterInternal(EmulatorComponent ec)
{
GpioPort gpioPort = ec as GpioPort;
if (gpioPort != null)
{
Debug.Assert(_ports[(int)gpioPort.Pin] == gpioPort);
_ports[(int)gpioPort.Pin] = null;
_validPorts.Remove(gpioPort);
base.UnregisterInternal(ec);
}
}
internal override void RegisterInternal(EmulatorComponent ec)
{
GpioPort port = ec as GpioPort;
if (port == null)
{
throw new Exception("Attempt to register a non GpioPort with GpioPortCollection.");
}
Cpu.Pin pin = port.Pin;
Debug.Assert(!(port is GpioPortNull));
if (Exists(pin))
{
throw new Exception("GPIO port " + pin + " is already set.");
}
_ports[(int)pin] = port;
_validPorts.Add(port);
base.RegisterInternal(ec);
}
internal bool Exists(Cpu.Pin pin)
{
GpioPort port = _ports[(int)pin];
return((port != null) && ((port is GpioPortNull) == false));
}
