CashDrawer (cd)

cd is a Go library designed to interface with the "USB TRIGGER for CASH DRAWER" BT-100U. It simplifies the process of opening a cash drawer using Go code.

Installation

To use the cd library in your Go project, you need to install it using:

go get github.com/Nimon77/cd

Usage

Here is a quick guide on how to use the cd library to control your cash drawer.

Opening the Cash Drawer

package main

import (
    "context"
    "log"
    "github.com/Nimon77/cd"
)

func main() {
    ctx := context.Background()
    
    // Initialize the CashDrawer manually with a specific port and baud rate
    drawer, err := cd.New("/dev/ttyUSB0", 9600)
    if err != nil {
        log.Fatal(err)
    }
    defer drawer.Close()

    // Open the cash drawer
    err = drawer.Open(ctx)
    if err != nil {
        log.Fatal(err)
    }

    log.Println("Cash drawer opened successfully!")
}

Automatically Detecting and Opening the Cash Drawer (linux only)

If you prefer the library to automatically detect the correct USB port, you can use the NewAuto function.

package main

import (
    "log"
    "github.com/Nimon77/cd"
)

func main() {
    // Automatically detect the cash drawer and initialize it
    drawer, err := cd.NewAuto()
    if err != nil {
        log.Fatal(err)
    }
    defer drawer.Close()

    // Open the cash drawer
    err = drawer.Open(context.Background())
    if err != nil {
        log.Fatal(err)
    }

    log.Println("Cash drawer opened successfully!")
}

Functions

`New(port string, baud int) (*CashDrawer, error)`

Creates a new CashDrawer instance with the specified serial port and baud rate.

port: The serial port to which the cash drawer is connected (e.g., /dev/ttyUSB0).
baud: The baud rate for the serial communication (e.g., 9600).

`NewAuto() (*CashDrawer, error)` (linux only)

Automatically detects the USB port connected to the cash drawer and initializes a new CashDrawer instance. This function scans the available USB devices and matches the correct one using predefined rules.

`Open(ctx context.Context) error`

Sends the command to open the cash drawer. It writes the necessary bytes to the serial port to trigger the drawer to open.

ctx: The context for managing request deadlines and cancellation signals.

`Close() error`

Closes the serial port connection to the cash drawer.

Dependencies

This library depends on the following packages:

github.com/citilinkru/libudev - For scanning and detecting USB devices. (linux only)
github.com/jacobsa/go-serial/serial - For handling serial port communications.

Make sure to include these dependencies in your project.

License

This project is licensed under the MIT License. See the LICENSE file for more details.

Contributions

Contributions are welcome! Please fork the repository and submit a pull request with your changes.

Support

If you encounter any issues or have questions, feel free to open an issue on GitHub.

Nimon77/cd