GPIO Library for ESP32

A GPIO (General Purpose Input/Output) library for BlueScript on ESP32. This package provides a high-level interface to control pins, read digital states, and handle hardware interrupts using the driver/gpio.h ESP-IDF APIs.

Installation

Install this package in your BlueScript project:

bscript project install https://github.com/bluescript-lang/pkg-gpio-esp32.git

Usage

Basic: Blink an LED

import * as time from "time";
import { GPIO, PinMode, PinLevel } from "gpio";

// Configure GPIO 2 (Onboard LED) as Output
const led = new GPIO(2, PinMode.Output);

while (true) {
    led.write(PinLevel.High);
    time.delay(500);
    led.write(PinLevel.Low);
    time.delay(500);
}

led.close();

Advanced: Button Interrupts

You can listen for changes on a pin (interrupts) without blocking the main loop.

import { GPIO, PinMode, PinLevel, PullMode, InterruptEdge, InterruptType } from "gpio";

const button = new GPIO(0, PinMode.Input);

// Handle button press (Falling edge)
button.onChange(InterruptEdge.Falling, InterruptType.Soft, () => {
    console.log("Button Pressed!");
});

API Reference

Class: GPIO

constructor(pin: integer, mode: PinMode)

Initializes a GPIO pin with the specified mode.

• pin: The GPIO number (e.g., 2, 23).
• mode: Initial PinMode (see Enums).

write(level: PinLevel): void

Sets the output level of the pin.

• level: PinLevel.High or PinLevel.Low.

read(): PinLevel

Reads the current level of the pin.

• Returns: PinLevel.High or PinLevel.Low.

setMode(mode: PinMode): void

Changes the pin mode dynamically.

setPullMode(mode: PullMode): void

Configures internal pull-up/pull-down resistors.

• mode: PullMode (see Enums).

onChange(edge: InterruptEdge, type: InterruptType, listener: () => void): void

Registers an interrupt handler function.

• edge: The trigger condition (Rising, Falling, or Change).
• type:
  • InterruptType.Soft: The listener runs on the Main Thread. Safe to use all BlueScript features (console.log, allocation, etc.).
  • InterruptType.Hard: The listener runs directly in the ISR (Interrupt Service Routine). extremely fast, but very restricted. Do not allocate memory or use heavy operations.
• listener: The callback function to execute.

offChange(): void

Removes the interrupt handler and disables the interrupt for this pin.

close(): void

Resets the pin and releases resources.

Enums

PinMode

Name	Value	Description
Input	0	Input only.
Output	1	Output only.
InputOutput	2	Both Input and Output.

PinLevel

Name	Value	Description
Low	0	0V (GND)
High	1	3.3V (VCC)

PullMode

Name	Value	Description
Floating	0	No pull resistor.
PullupOnly	1	Internal pull-up enabled.
PulldownOnly	2	Internal pull-down enabled.
PullupPulldown	3	Both pull-up and pull-down enabled.

InterruptEdge

Name	Value	Description
Rising	0	Triggers when signal goes Low → High.
Falling	1	Triggers when signal goes High → Low.
Change	2	Triggers on any change.

InterruptType

Name	Value	Description
Soft	0	Queues event to Main Thread (Recommended).
Hard	1	Runs inside ISR (Advanced use only).