Example #1
0
// Open connects to the given serial port.
func (p *port) Open(c *Config) (err error) {
	handle, err := newHandle(c)
	if err != nil {
		return
	}
	// Read and write timeout
	if c.Timeout > 0 {
		timeout := C.DWORD(c.Timeout.Nanoseconds() / 1E6)
		var timeouts C.COMMTIMEOUTS
		// wait until a byte arrived or time out
		timeouts.ReadIntervalTimeout = C.MAXDWORD
		timeouts.ReadTotalTimeoutMultiplier = C.MAXDWORD
		timeouts.ReadTotalTimeoutConstant = timeout
		timeouts.WriteTotalTimeoutMultiplier = 0
		timeouts.WriteTotalTimeoutConstant = timeout
		if C.SetCommTimeouts(C.HANDLE(handle), &timeouts) == 0 {
			err = fmt.Errorf("serial: could not set timeout: %v", syscall.GetLastError())
			syscall.CloseHandle(handle)
			return
		}
	}
	p.handle = handle
	return
}
Example #2
0
func main() {
	handle, err := syscall.CreateFile(syscall.StringToUTF16Ptr(port),
		syscall.GENERIC_READ|syscall.GENERIC_WRITE,
		0,   // mode
		nil, // security
		syscall.OPEN_EXISTING, // no creating new
		0,
		0)
	if err != nil {
		fmt.Print(err)
		return
	}
	fmt.Printf("handle created %d\n", handle)
	defer syscall.CloseHandle(handle)

	var dcb C.DCB
	dcb.BaudRate = 9600
	dcb.ByteSize = 8
	dcb.StopBits = C.ONESTOPBIT
	dcb.Parity = C.NOPARITY
	if C.SetCommState(C.HANDLE(handle), &dcb) == 0 {
		fmt.Printf("set comm state error %v\n", syscall.GetLastError())
		return
	}
	fmt.Printf("set comm state succeed\n")

	var timeouts C.COMMTIMEOUTS
	// time-out between charactor for receiving (ms)
	timeouts.ReadIntervalTimeout = 1000
	timeouts.ReadTotalTimeoutMultiplier = 0
	timeouts.ReadTotalTimeoutConstant = 1000
	timeouts.WriteTotalTimeoutMultiplier = 0
	timeouts.WriteTotalTimeoutConstant = 1000
	if C.SetCommTimeouts(C.HANDLE(handle), &timeouts) == 0 {
		fmt.Printf("set comm timeouts error %v\n", syscall.GetLastError())
		return
	}
	fmt.Printf("set comm timeouts succeed\n")

	var n uint32
	data := []byte("abc")
	err = syscall.WriteFile(handle, data, &n, nil)
	if err != nil {
		fmt.Println(err)
		return
	}
	fmt.Printf("write file succeed\n")
	fmt.Printf("Press Enter when ready for reading...")
	reader := bufio.NewReader(os.Stdin)
	_, _ = reader.ReadString('\n')

	data = make([]byte, 512)
	err = syscall.ReadFile(handle, data, &n, nil)
	if err != nil {
		fmt.Println(err)
		return
	}
	fmt.Printf("received data %v:\n", n)
	fmt.Printf("%x\n", data[:n])
	fmt.Printf("closed\n")
}