114 lines
2.9 KiB
Go
114 lines
2.9 KiB
Go
//
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// Copyright 2014-2023 Cristian Maglie. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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//
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/*
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Package serial is a cross-platform serial library for the go language.
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The canonical import for this library is go.bug.st/serial so the import line
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is the following:
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import "go.bug.st/serial"
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It is possible to get the list of available serial ports with the
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GetPortsList function:
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ports, err := serial.GetPortsList()
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if err != nil {
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log.Fatal(err)
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}
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if len(ports) == 0 {
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log.Fatal("No serial ports found!")
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}
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for _, port := range ports {
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fmt.Printf("Found port: %v\n", port)
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}
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The serial port can be opened with the Open function:
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mode := &serial.Mode{
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BaudRate: 115200,
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}
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port, err := serial.Open("/dev/ttyUSB0", mode)
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if err != nil {
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log.Fatal(err)
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}
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The Open function needs a "mode" parameter that specifies the configuration
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options for the serial port. If not specified the default options are 9600_N81,
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in the example above only the speed is changed so the port is opened using 115200_N81.
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The following snippets shows how to declare a configuration for 57600_E71:
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mode := &serial.Mode{
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BaudRate: 57600,
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Parity: serial.EvenParity,
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DataBits: 7,
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StopBits: serial.OneStopBit,
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}
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The configuration can be changed at any time with the SetMode function:
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err := port.SetMode(mode)
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if err != nil {
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log.Fatal(err)
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}
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The port object implements the io.ReadWriteCloser interface, so we can use
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the usual Read, Write and Close functions to send and receive data from the
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serial port:
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n, err := port.Write([]byte("10,20,30\n\r"))
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if err != nil {
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log.Fatal(err)
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}
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fmt.Printf("Sent %v bytes\n", n)
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buff := make([]byte, 100)
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for {
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n, err := port.Read(buff)
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if err != nil {
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log.Fatal(err)
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break
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}
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if n == 0 {
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fmt.Println("\nEOF")
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break
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}
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fmt.Printf("%v", string(buff[:n]))
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}
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If a port is a virtual USB-CDC serial port (for example an USB-to-RS232
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cable or a microcontroller development board) is possible to retrieve
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the USB metadata, like VID/PID or USB Serial Number, with the
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GetDetailedPortsList function in the enumerator package:
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import "go.bug.st/serial/enumerator"
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ports, err := enumerator.GetDetailedPortsList()
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if err != nil {
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log.Fatal(err)
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}
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if len(ports) == 0 {
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fmt.Println("No serial ports found!")
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return
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}
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for _, port := range ports {
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fmt.Printf("Found port: %s\n", port.Name)
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if port.IsUSB {
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fmt.Printf(" USB ID %s:%s\n", port.VID, port.PID)
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fmt.Printf(" USB serial %s\n", port.SerialNumber)
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}
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}
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for details on USB port enumeration see the documentation of the specific package.
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This library tries to avoid the use of the "C" package (and consequently the need
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of cgo) to simplify cross compiling.
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Unfortunately the USB enumeration package for darwin (MacOSX) requires cgo
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to access the IOKit framework. This means that if you need USB enumeration
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on darwin you're forced to use cgo.
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*/
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package serial
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