---
id: TASK-128
title: Pico firmware — servo + LED drivers
status: Done
assignee: []
created_date: '2026-03-29 20:51'
labels:
  - firmware
  - hardware
milestone: m-2
dependencies: []
priority: high
---

## Description

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Write config.py, servo_driver.py (PCA9685 I2C, smooth interpolation), and led_driver.py (GPIO PWM brightness) for Raspberry Pi Pico.
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## Acceptance Criteria
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- [ ] #1 PCA9685 init at 50Hz, set_angle with 500-2500us mapping
- [ ] #2 Smooth interpolation in configurable degree steps
- [ ] #3 LED PWM 0-255, blink helper, deinit cleanup
- [ ] #4 Config centralises all pin/calibration constants
<!-- AC:END -->

## Final Summary

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Three firmware files: config.py (constants), servo_driver.py (PCA9685 two-class design with smooth interp), led_driver.py (hardware PWM on GP15).
<!-- SECTION:FINAL_SUMMARY:END -->