/// <summary>
/// Writes the "on" and "off" values of a channel together, and updates it in <see cref="Channels"/>.
/// </summary>
/// <param name="index">Zero based channel number (0-15) or 16 for the "all call" channel.</param>
/// <param name="value"><see cref="NxpPca9685ChannelValue"/> to write.</param>
/// <returns>
/// Updated channel value or null when all channels were updated.
/// </returns>
public NxpPca9685Channel WriteChannel(int index, NxpPca9685ChannelValue value)
{
// Validate
if (index <0 | index> ChannelCount)
{
throw new ArgumentOutOfRangeException(nameof(index));
}
// Validate
if (value.On > NxpPca9685ChannelValue.Maximum + 1 ||
value.Off > NxpPca9685ChannelValue.Maximum + 1)
{
throw new ArgumentOutOfRangeException(nameof(value));
}
// Calculate register address
var register = GetChannelAddress(index);
// Convert and write value
var bytes = value.ToByteArray();
Hardware.WriteJoinBytes(register, bytes);
// Read and return result
if (index < ChannelCount)
{
return(ReadChannel(index));
}
ReadAllChannels();
return(null);
}
/// <summary>
/// Calculates the "on" and "off" values of a channel from milliseconds (and optional delay),
/// then writes them together, and updates it in <see cref="Channels"/>.
/// </summary>
/// <param name="index">Zero based channel number (0-15) or 16 for the "all call" channel.</param>
/// <param name="length">
/// Pulse length in milliseconds. Cannot be greater than one clock interval (1000 / frequency).
/// </param>
/// <param name="delay">Optional delay in milliseconds. Cannot be greater than one clock interval (1000 / frequency).</param>
/// <returns>
/// Updated channel value or null when all channels were updated.
/// </returns>
public NxpPca9685Channel WriteChannelMilliseconds(int index, float length, float delay = 0)
{
// Read current frequency
var frequency = ReadFrequency();
// Call overloaded method
return(WriteChannel(index, NxpPca9685ChannelValue.FromMilliseconds(length, frequency, delay)));
}
/// <summary>
/// Reads the pre-scale register and calculates the <see cref="Frequency"/> (and related properties)
/// based on <see cref="ClockSpeed"/>.
/// </summary>
/// <returns>
/// Frequency in Hz. Related properties are also udpated.
/// </returns>
public float ReadFrequency()
{
// Read pre-scale register
var preScale = Hardware.WriteReadByte((byte)NxpPca9685Register.PreScale);
// Calculate frequency
var frequency = CalculateFrequency(preScale, ClockSpeed);
// Update related properties
Frequency = frequency;
PwmMsMinimum = NxpPca9685ChannelValue.CalculateMilliseconds(Frequency, 0);
PwmMsMaximum = NxpPca9685ChannelValue.CalculateMilliseconds(Frequency, NxpPca9685ChannelValue.Maximum);
// Return result
return(frequency);
}
/// <summary>
/// Sets RGB values of the high intensity LED together (in one operation).
/// </summary>
/// <remarks>
/// Automatically inverts the value, providing a natural behaviour where a higher number
/// produces a higher LED intensity. Normally, when written as raw PWM values, the output
/// is inverted due to common anode.
/// </remarks>
/// <param name="red">Red value in the range 0-<see cref="NxpPca9685ChannelValue.Maximum"/>.</param>
/// <param name="green">Green value in the range 0-<see cref="NxpPca9685ChannelValue.Maximum"/>.</param>
/// <param name="blue">Blue value in the range 0-<see cref="NxpPca9685ChannelValue.Maximum"/>.</param>
public void SetLed(int red, int green, int blue)
{
// Validate
if (red < 0 || red > NxpPca9685ChannelValue.Maximum)
{
throw new ArgumentOutOfRangeException(nameof(red));
}
if (green < 0 || green > NxpPca9685ChannelValue.Maximum)
{
throw new ArgumentOutOfRangeException(nameof(green));
}
if (blue < 0 || blue > NxpPca9685ChannelValue.Maximum)
{
throw new ArgumentOutOfRangeException(nameof(blue));
}
// Invert values
var inverseRed = ~red & 0x0fff;
var inverseGreen = ~green & 0x0fff;
var inverseBlue = ~blue & 0x0fff;
// Build block of data which sets all three register high and low values
var redBytes = NxpPca9685ChannelValue.FromLength(inverseRed).ToByteArray();
var greenBytes = NxpPca9685ChannelValue.FromLength(inverseGreen).ToByteArray();
var blueBytes = NxpPca9685ChannelValue.FromLength(inverseBlue).ToByteArray();
var data = new byte[1 + ChannelSize * 3];
data[0] = ChannelStartAddress;
Array.ConstrainedCopy(blueBytes, 0, data, 1, ChannelSize);
Array.ConstrainedCopy(greenBytes, 0, data, 1 + ChannelSize, ChannelSize);
Array.ConstrainedCopy(redBytes, 0, data, 1 + ChannelSize * 2, ChannelSize);
// Set new value
Hardware.Write(data);
// Update properties
ReadLed();
}
/// <summary>
/// Writes the "on" and "off" values of a channel together, and updates it in <see cref="Channels"/>.
/// </summary>
/// <param name="index">Zero based channel number (0-15) or 16 for the "all call" channel.</param>
/// <param name="value"><see cref="NxpPca9685ChannelValue"/> to write.</param>
/// <returns>
/// Updated channel value or null when all channels were updated.
/// </returns>
public NxpPca9685Channel WriteChannel(int index, NxpPca9685ChannelValue value)
{
// Validate
if (index < 0 | index > ChannelCount) throw new ArgumentOutOfRangeException(nameof(index));
// Validate
if (value.On > NxpPca9685ChannelValue.Maximum + 1 ||
value.Off > NxpPca9685ChannelValue.Maximum + 1)
throw new ArgumentOutOfRangeException(nameof(value));
// Calculate register address
var register = GetChannelAddress(index);
// Convert and write value
var bytes = value.ToByteArray();
Hardware.WriteJoinBytes(register, bytes);
// Read and return result
if (index < ChannelCount)
return ReadChannel(index);
ReadAllChannels();
return null;
}
/// <summary>
/// Calculates the "on" and "off" values of a channel from length (and optional delay),
/// then writes them together, and updates it in <see cref="Channels"/>.
/// </summary>
/// <param name="index">Zero based channel number (0-15) or 16 for the "all call" channel.</param>
/// <param name="length">Pulse length in clock ticks.</param>
/// <param name="delay">Optional delay in clock ticks.</param>
/// <returns>
/// Updated channel value or null when all channels were updated.
/// </returns>
public NxpPca9685Channel WriteChannelLength(int index, int length, int delay = 0)
{
// Call overloaded method
return(WriteChannel(index, NxpPca9685ChannelValue.FromLength(length, delay)));
}
/// <summary>
/// Creates an instance with the specified values.
/// </summary>
public NxpPca9685Channel(int index, NxpPca9685ChannelValue value)
{
Index = index;
Value = value;
Value.Changed += OnValueChanged;
}
/// <summary>
/// Creates an instance with the specified values.
/// </summary>
public NxpPca9685Channel(int index, NxpPca9685ChannelValue value)
{
Index = index;
Value = value;
Value.Changed += OnValueChanged;
}
