private void Start(LedChannelCount channelCount)
{
channels = (int)channelCount;
currentValue = new BitArray(channels);
for (var i = 0; i < channels; i++)
{
Leds.Add(new Led(this, i));
}
if (oe != null)
{
oe.MakeDigitalPushPullOutAsync();
oe.DigitalValue = false;
HasGlobalBrightnessControl = false;
}
else if (oePwm != null)
{
oePwm.EnablePwmAsync();
oePwm.PulseWidth = 0;
HasGlobalBrightnessControl = true;
}
else
{
HasGlobalBrightnessControl = false;
}
HasIndividualBrightnessControl = false;
Brightness = 1.0; // turn on the display
}
/// <summary>
/// Construct an LED shift register attached to the output of another shift register
/// </summary>
/// <param name="upstreamDevice">The upstream device this shift register is attached to</param>
/// <param name="OutputEnablePin">The digital pin to use, if any, to control the display state</param>
/// <param name="ChannelCount">The number of channels this LED shift register has</param>
public LedShiftRegister(ChainableShiftRegisterOutput upstreamDevice,
LedChannelCount ChannelCount = LedChannelCount.SixteenChannel, DigitalOut OutputEnablePin = null) : base(
upstreamDevice, (int)ChannelCount / 8)
{
oe = OutputEnablePin;
Start(ChannelCount);
}
/// <summary>
/// Construct an LED shift register attached to the output of another shift register
/// </summary>
/// <param name="upstreamDevice">The upstream device this shift register is attached to</param>
/// <param name="OutputEnablePin">The PWM pin to use, if any, to control the display brightness</param>
/// <param name="ChannelCount">The number of channels this LED shift register has</param>
public LedShiftRegister(ChainableShiftRegisterOutput upstreamDevice, Pwm OutputEnablePin,
LedChannelCount ChannelCount = LedChannelCount.SixteenChannel) : base(upstreamDevice,
(int)ChannelCount / 8)
{
oePwm = OutputEnablePin;
Start(ChannelCount);
}
/// <summary>
/// Construct an LED shift register attached directly to a board SPI module
/// </summary>
/// <param name="SpiModule">The board's SPI module</param>
/// <param name="LatchPin">The pin to use for latches</param>
/// <param name="OutputEnablePin">The PWM pin to use, allowing controllable global brightness.</param>
/// <param name="ChannelCount">The number of channels this LED shift register has</param>
/// <param name="speedMhz">The speed, in MHz, to use when communicating</param>
public LedShiftRegister(Spi SpiModule, SpiChipSelectPin LatchPin, Pwm OutputEnablePin,
LedChannelCount ChannelCount = LedChannelCount.SixteenChannel, double speedMhz = 6) : base(SpiModule,
LatchPin, (int)ChannelCount / 8, speedMhz)
{
oePwm = OutputEnablePin;
Start(ChannelCount);
}