Micropython Skillsalgorithm

On-Device Algorithms

Pure MicroPython algorithm implementations that run on the device. These are Safe tier — no direct hardware side effects.

These algorithms are typically combined with sensor reads (input) and actuator control (output). Upload as .py files via mpremote fs cp algorithm.py : for reuse.

PID Controller

Classic PID with anti-windup for control loops (e.g., temperature regulation):

import time, json

class PID:
    def __init__(self, kp, ki, kd, setpoint=0, output_min=-100, output_max=100):
        self.kp = kp
        self.ki = ki
        self.kd = kd
        self.setpoint = setpoint
        self.output_min = output_min
        self.output_max = output_max
        self._integral = 0
        self._last_error = 0
        self._last_time = time.ticks_ms()

    def compute(self, measurement):
        now = time.ticks_ms()
        dt = time.ticks_diff(now, self._last_time) / 1000.0
        if dt <= 0:
            dt = 0.001
        self._last_time = now

        error = self.setpoint - measurement
        self._integral += error * dt
        derivative = (error - self._last_error) / dt
        self._last_error = error

        output = self.kp * error + self.ki * self._integral + self.kd * derivative

        # Anti-windup: clamp output and freeze integral if saturated
        if output > self.output_max:
            output = self.output_max
            self._integral -= error * dt
        elif output < self.output_min:
            output = self.output_min
            self._integral -= error * dt

        return output

# Example usage: temperature control