Pamoja.Actuators 0.1.18

Pamoja.Actuators

PCA9685 PWM and servo pulses, and stepper coil sequencing. One capability of pamoja, one memory-safe Rust core with bindings for TypeScript, Python, and C#.

Install

dotnet add package Pamoja.Actuators

using Pamoja.Actuators;

This pulls in Pamoja.Native, the compiled engine. dotnet add package Pamoja is the whole framework in one package.

Example

The guide project's example, spliced here as it ran in CI.

From bindings/dotnet/samples/Pamoja.Guides/ActuatorsGuide.cs:

// A servo bank wants 50 Hz. The prescale register that produces it is derived
// from the part's 25 MHz internal oscillator, so a caller names the rate it wants
// rather than working the divider out.
byte prescale = Pca9685.PrescaleForFrequency(50);
Console.WriteLine(
    $"prescale  {prescale} gives {Pca9685.FrequencyForPrescale(prescale):F1} Hz");

// Each channel owns four consecutive registers, so a whole channel is written in
// one bus transaction rather than four.
Console.WriteLine($"channel 3 starts at register 0x{Pca9685.ChannelRegister(3):X2}");

// A centered hobby servo holds its output high for 1500 us of the 20 ms period.
// The part counts in 4096 steps per period, so that is where the pulse ends.
byte[] centered = Pwm.Servo(1500, 50);
Console.WriteLine($"centered servo goes low at count {Pwm.Counts(centered).Off} of 4096");

// Fully off carries its own flag rather than a zero duty, which would still hold
// the output high for the first count of every period.
bool flagged = Pwm.Counts(Pwm.FullOff()).Off != Pwm.Counts(Pwm.Duty(0)).Off;
Console.WriteLine($"full off flag set: {flagged}");

// A stepper is driven by walking a pattern of coil states. Half-step drive
// interleaves the one-coil and two-coil patterns, so it has twice as many.
using var motor = new Stepper(StepDrive.HalfStep);
Console.WriteLine($"coils     {Convert.ToString(motor.Coils, 2).PadLeft(4, '0')} at rest");
for (int step = 0; step < 2; step++)
{
    byte coils = motor.Step(StepDirection.Forward);
    Console.WriteLine(
        $"coils     {Convert.ToString(coils, 2).PadLeft(4, '0')} after a step");
}

// The patterns wrap, so the motor runs indefinitely either way, and an angle
// converts to whole steps: a quarter turn of a 1.8-degree motor is fifty of them.
for (int step = 2; step < Stepper.StepCount(StepDrive.HalfStep); step++)
{
    motor.Step(StepDirection.Forward);
}

Console.WriteLine(
    $"coils     {Convert.ToString(motor.Coils, 2).PadLeft(4, '0')} back at the start "
    + "of the cycle");
Console.WriteLine($"a quarter turn is {Stepper.StepsForDegrees(90.0f, 200)} steps");

The same capability in every language

Documentation

• Pamoja.Actuators reference, every type in this namespace.
• The Actuator drivers guide, with the same example in Rust, TypeScript, and Python.
• Every capability, and the install page.

License

MIT