v1.2.1

Bug Fix

• Fix stopped fan detection - EMC2305 returns near-max tach count (~1022) when no tach signal is detected. Added TACH_COUNT_STOPPED_THRESHOLD to correctly return 0 RPM for stopped fans.

Installation

pip install microchip-emc2305==1.2.1

v1.2.0

Changes

• Fix RPM calculation formula - Add missing (edges-1) factor to numerator
• Apply 3-bit right shift to TACH register values (bits 7:3 contain the count)
• Add TACH_COUNT_LOW_SHIFT constant for register handling
• Comprehensive tachometer documentation in CLAUDE.md and README.md
• New USER_GUIDE.md with complete usage instructions

Tachometer Configuration

Fan Type	Pulses/Rev	edges Setting
1-pole	1	edges=3
2-pole	2	edges=5
3-pole	3	edges=7
4-pole	4	edges=9

Installation

pip install microchip-emc2305==1.2.0

v1.1.0

What's Changed

Added

• set_pwm_output_mode() - Configure PWM output as open-drain or push-pull per channel
• set_all_pwm_output_mode() - Configure PWM output mode for all channels at once
• get_pwm_output_mode() - Read current PWM output mode for a channel
• set_pwm_polarity() - Configure PWM polarity (normal/inverted) per channel
• get_pwm_polarity() - Read current PWM polarity for a channel
• MIN_VALID_RPM_READING constant (200 RPM) for tachometer noise filtering

Fixed

• Critical: PWM output mode register (0x2B) logic was inverted. Per datasheet: 0=open-drain (default), 1=push-pull. Previous implementation had this backwards.
• RPM readings below 200 RPM now return 0 (filters tachometer noise when fan is stopped)

Installation

pip install microchip-emc2305==1.1.0

Full Changelog: v1.0.0...v1.1.0

v1.0.0 - First Stable Release

microchip-emc2305 v1.0.0

First stable release of the Python driver for Microchip EMC2305 5-channel PWM fan controller.

Features

• 5 independent PWM channels - Control up to 5 fans simultaneously
• Dual control modes:
  • PWM Mode: Direct duty cycle control (0-100%)
  • FSC Mode: Closed-loop RPM control with hardware PID
• Per-fan PWM frequency - Individual frequency control per channel
• RPM monitoring - Real-time tachometer reading
• Fault detection - Stall, spin failure, aging fan detection
• SMBus Alert (ALERT#) - Hardware interrupt support
• Software configuration lock - Protect settings in production
• Cross-process I2C locking - Safe multi-process access
• Thread-safe operation - Concurrent access protection

Installation

pip install microchip-emc2305

# With YAML config support
pip install microchip-emc2305[config]

Supported Platforms

• Linux with I2C support
• Raspberry Pi, Banana Pi, and other embedded Linux systems
• Python 3.9+

Documentation

See the README for full documentation and examples.