drivers.reflectance module

class drivers.reflectance.Reflectance_Sensor(analogPins)

Bases: object

Driver for a reflectance sensor array read through ADC channels.

The class provides:

• one-shot raw + normalized sensor reads (get_values)

• calibration file loading (load_calibration_from_file)

• cooperative calibration sampling (calibrate) via yield

calibrate(mode)

Cooperative calibration generator.

mode should be “light” or “dark”. The routine collects _SAMPLE_COUNT raw samples and stores the per-sensor average to file. It yields frequently so other cotasks can continue running.

After calibration completes, the in-memory cache is updated.

get_centroid()

get_values()

Return (raw, calibrated, C, line_detected) where: - raw: list of averaged raw ADC values - calibrated: list of normalized sensor values (0=white, 1=black) - C: weighted line position (centroid) - line_detected: True if line is detected, False if lost (noise/uniform)

Raw values are averaged over _READ_SAMPLES reads to reduce noise. When line is lost, C returns the last valid centroid.

load_calibration_from_file(filename)

Load calibration file into self._calibration.

The on-disk format must be a list of dicts with ‘dark’ and ‘light’ keys (the format produced by calibrate).