Why

The ESP32 Family of chips have a large set of peripherals, that can provide different features, while not being bound to particular GPIOs. Some peripherals can provide more than one functionality and there are functionalities that can be provided by different peripherals at the same time (ex. LEDC can provide PWM, Servo and Tone, so can RMT, but RMT can also provide NeoPixel and others). Different chips have different subset of peripherals and peripherals themselves have different number of channels, limits, etc.

With Peripheral Manager we hope to provide tracking of available GPIOs, peripherals and channels, in order to have a cleaner and easy to use API with more features on more pins, as well as preventing some common mistakes, like using pins reserved for Flash and PSRAM.

Targets

• Support analogWrite on more channels
• Support Servo on more channels
• Support Tone on more channels
• Prevent use of reserved pins
• Add more output/input options (ex. NeoPixel, OneWire, etc.)

Feature Ideas

• Allow GPIO remapping, like on other MCUs
• Allow picking the most appropriate peripheral for given functionality (ex. RMT will provide better Servo than LEDC)
• Allow switching the peripheral if needed for higher priority functionality (ex. switch Servo channel from RMT to LEDC if channel for NeoPixel is needed)
• Have LEDC select an already configured timer, if it matches the requirements (ex. all analogWrite channels can use the same timer. Same goes for Servo)
• Output error if pin is invalid, reserved or already attached to another peripheral
• Provide API to get GPIO/peripheral status and availability
• Keep backward compatibility (ex. libs that use LEDC and have already predefined channel)