---
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

<!-- SECTION:DESCRIPTION:BEGIN -->
Write config.py, servo_driver.py (PCA9685 I2C, smooth interpolation), and led_driver.py (GPIO PWM brightness) for Raspberry Pi Pico.
<!-- SECTION:DESCRIPTION:END -->

## Acceptance Criteria
<!-- AC:BEGIN -->
- [ ] #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

<!-- SECTION:FINAL_SUMMARY:BEGIN -->
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 -->
