/// <summary>
/// Write a GrovePi command
/// </summary>
/// <param name="command">The GrovePi command</param>
/// <param name="pin">The pin to write the command</param>
/// <param name="param1">First parameter</param>
/// <param name="param2">Second parameter</param>
public void WriteCommand(GrovePiCommand command, GrovePort pin, byte param1, byte param2)
{
Span <byte> outArray = stackalloc byte[4]
{
(byte)command, (byte)(pin), param1, param2
};
byte tries = 0;
IOException innerEx = null;
// When writing/reading to the I2C port, GrovePi doesn't respond on time in some cases
// So we wait a little bit before retrying
// In most cases, the I2C read/write can go thru without waiting
while (tries < MaxRetries)
{
try
{
_i2cDevice.Write(outArray);
return;
}
catch (IOException ex)
{
// Give it another try
innerEx = ex;
tries++;
Thread.Sleep(10);
}
}
throw new IOException($"{nameof(WriteCommand)}: Failed to write command {command}", innerEx);
}
/// <summary>
/// Read data from GrovePi
/// </summary>
/// <param name="command">The GrovePi command</param>
/// <param name="pin">The pin to read</param>
/// <returns></returns>
public byte[] ReadCommand(GrovePiCommand command, GrovePort pin)
{
int numberBytesToRead = 0;
switch (command)
{
case GrovePiCommand.DigitalRead:
numberBytesToRead = 1;
break;
case GrovePiCommand.AnalogRead:
case GrovePiCommand.UltrasonicRead:
case GrovePiCommand.LetBarGet:
numberBytesToRead = 3;
break;
case GrovePiCommand.Version:
numberBytesToRead = 4;
break;
case GrovePiCommand.DhtTemp:
numberBytesToRead = 9;
break;
// No other commands are for read
default:
return(null);
}
byte[] outArray = new byte[numberBytesToRead];
byte tries = 0;
IOException innerEx = null;
// When writing/reading the I2C port, GrovePi doesn't respond on time in some cases
// So we wait a little bit before retrying
// In most cases, the I2C read/write can go thru without waiting
while (tries < MaxRetries)
{
try
{
_i2cDevice.Read(outArray);
return(outArray);
}
catch (IOException ex)
{
// Give it another try
innerEx = ex;
tries++;
Thread.Sleep(10);
}
}
throw new IOException($"{nameof(ReadCommand)}: Failed to write command {command}", innerEx);
}
/// <summary>
/// Read data from GrovePi
/// </summary>
/// <param name="command">The GrovePi command</param>
/// <param name="pin">The pin to read</param>
/// <returns></returns>
public byte[]? ReadCommand(GrovePiCommand command, GrovePort pin)
{
int numberBytesToRead = command switch
{
GrovePiCommand.DigitalRead => 1,
GrovePiCommand.AnalogRead or GrovePiCommand.UltrasonicRead or GrovePiCommand.LetBarGet => 3,
GrovePiCommand.Version => 4,
GrovePiCommand.DhtTemp => 9,
_ => 0,
};
if (numberBytesToRead == 0)
{
return(null);
}
byte[] outArray = new byte[numberBytesToRead];
byte tries = 0;
IOException?innerEx = null;
// When writing/reading the I2C port, GrovePi doesn't respond on time in some cases
// So we wait a little bit before retrying
// In most cases, the I2C read/write can go thru without waiting
while (tries < MaxRetries)
{
try
{
_i2cDevice.Read(outArray);
return(outArray);
}
catch (IOException ex)
{
// Give it another try
innerEx = ex;
tries++;
Thread.Sleep(10);
}
}
throw new IOException($"{nameof(ReadCommand)}: Failed to write command {command}", innerEx);
}
