dxDriver

1. Overview

dxDriver is one of the core basic modules of DejaOS.
It provides a unified entry point for all device‑specific hardware drivers, combining a JavaScript configuration file (dxDriver.js) with a set of native driver .so libraries.

• Defines all hardware resource mappings for a specific device model (GPIO pins, UART paths, camera devices, PWM channels, etc.).
• Loads the corresponding native driver libraries that actually drive the hardware.
• Is required in almost all real devices and should be enabled by default in DejaOS projects.

2. Files

• dxDriver.js
• Multiple *.so files

Ensure all these files are included under the dxmodules subdirectory of your project root.

3. Dependencies

4. Compatible Devices

Compatible with all devices running dejaOS v2.0+.

5. Configuration Structure

Below is a simplified example from the DW200 device:

const dxDriver = {};

// 1) GPIO pins
dxDriver.GPIO = {
  // Relay control
  RELAY: 35,
};

// 2) Communication channels
dxDriver.CHANNEL = {
  // RS‑485 UART
  UART_PATH: "/dev/ttyS3",
  // USB HID virtual device
  USBHID_PATH: "/dev/hidg1",
};

// 3) Camera parameters
dxDriver.CAPTURER = {
  WIDTH: 800,
  HEIGHT: 600,
  PATH: "/dev/video11",
};

// 4) PWM channel for buzzer
dxDriver.PWM = {
  BEEP_CHANNEL: 4,
  BEEP_GPIO: 130,
  BEEP_PERIOD_NS: 366166,
  BEEP_DUTY: (366166 * 50) / 255,
};

export default dxDriver;

Each device can define its own sections (e.g. GPIO, CHANNEL, CAPTURER, PWM, etc.) according to its hardware design.

6. Usage

6.1 Importing dxDriver

import dxDriver from "./dxmodules/dxDriver.js";

// Example: use GPIO resource to control a relay
const relayPin = dxDriver.GPIO.RELAY;
// Pass relayPin to your GPIO abstraction (e.g. dxGpio) to drive the hardware

Typical patterns:

• Use dxDriver.GPIO constants when configuring dxGpio / dxGpioKey.
• Use dxDriver.CHANNEL.UART_PATH when configuring serial communication modules.
• Use dxDriver.CAPTURER when initializing camera modules.
• Use dxDriver.PWM when controlling buzzers or LEDs via dxPwm.

7. Best Practices

• Treat dxDriver as the single source of truth for all hardware resource definitions in your project.
• Avoid hard‑coding GPIO numbers or /dev/... paths elsewhere in your code; always reference them through dxDriver.
• For new hardware revisions, create a separate dxDriver.js variant (and driver .so set) to keep configurations clean and maintainable.