v1.8.5 - Fix ESP32-C3 fan PWM and tachometer issues
ESP32-C3 Pinout Fix
This release fixes the fan PWM and tachometer issues on ESP32-C3 SuperMini boards.
Problem
- Fan was running slowly/weakly regardless of PWM setting
- Tachometer was reporting extremely high RPM values (noise)
Root Cause
- GPIO5 (previous FAN_PWM) is an ADC2 pin which has interference when WiFi is active on ESP32
- GPIO6 (previous FAN_TACHO) is JTAG MTCK which was picking up noise
Solution
Moved fan control to ADC1 pins which don't conflict with WiFi:
| Function | Old Pin | New Pin | Reason |
|---|---|---|---|
| Fan PWM | GPIO5 | GPIO3 | ADC1, no WiFi interference |
| Fan Tacho | GPIO6 | GPIO4 | ADC1, clean interrupt support |
Soldering Changes Required
If you have an ESP32-C3 SuperMini with the old wiring, you need to re-solder:
Blue wire (PWM) → GPIO3 (was GPIO5)
Yellow wire (Tacho) → GPIO4 (was GPIO6)
Other Changes
- Added Arduino-ESP32 v3.x LEDC API compatibility
Full ESP32-C3 SuperMini Pinout
| GPIO | Function | Description |
|---|---|---|
| GPIO3 | Fan PWM | Speed control (ADC1, safe) |
| GPIO4 | Fan Tacho | RPM feedback (ADC1, interrupt) |
| GPIO10 | LED | WS2812 RGB LED |
| GPIO0 | SW2 | Connect button |
| GPIO1 | SW1 | Cold reset button |