Open/close a serial port

The SerialPortManager allows you to create a SerialPort object for a specific port name. The listSerialPorts() method lists all the available serial ports in the device.

You can also specify other serial port parameters using a SerialPortParameters object or directly in the openSerialPort method.

Method	Description
openSerialPort(String)	Creates and opens a SerialPort object for the provided port name
openSerialPort(String, SerialPortParameters)	Creates and opens a SerialPort object for the provided port name with the given configuration
openSerialPort(String, int, int, int, int, int, int)	Creates and opens a SerialPort object for the provided port name with the given port parameters

When they are not specified, the serial port parameter default values are the following:

• Baud rate: 9600
• Data bits: 8
• Stop bits: 1
• Parity: None
• Flow control: None
• Read timeout: 3 seconds

Note The SerialPort class includes constant definitions for the possible values of data bits, stop bits, parity, and flow control. For example: SerialPort.DATABITS_8, SerialPort.STOPBITS_1, SerialPort.PARITY_NONE, SerialPort.FLOWCONTROL_NONE.

The three methods that open the serial port may fail for the following reasons:

• If the serial port name is invalid or does not exist, the openSerialPort() method throws a NoSuchPortException.
• If the serial port is already in use by other application(s), the openSerialPort() method throws a PortInUseException.

Opening serial ports 

import com.digi.android.serial.SerialPort;
import com.digi.android.serial.SerialPortManager;
import com.digi.android.serial.SerialPortParameters;

[...]

SerialPortManager serialPortManager = ...;

// Get the list of available serial ports.
String[] portNames = serialPortManager.listSerialPorts(); 

// Define a serial configuration: 115200/8/N/1 and hardware flow control.
SerialPortParameters params = new SerialPortParameters(
		9600,			     					      /* baudrate:     9600 */
		SerialPort.DATABITS_8,						      /* data bits:    8 */
		SerialPort.STOPBITS_1,						      /* stop bits:    1 */
		SerialPort.PARITY_NONE,		     				      /* parity:       none */
		SerialPort.FLOWCONTROL_RTSCTS_IN | SerialPort.FLOWCONTROL_RTSCTS_OUT, /* flow ctrl:    hardware */
		2000								      /* read timeout: 2s */);

// Open the available serial ports with the previous configuration.
SerialPorts[] ports = new SerialPorts[portNames.length];
for (int i = 0; i < portNames.length; i++)
	ports[i] = serialPortManager.openSerialPort(portNames[i], params);

[...]

Once you have finished with a serial port, you must close it. This frees the port so that other applications can use it.

To close a serial port, use the close() method of the SerialPort object.

Closing serial ports 

import com.digi.android.serial.SerialPort;
import com.digi.android.serial.SerialPortManager;
 
[...]
 
SerialPortManager serialPortManager = ...;
SerialPort port = ...;
 
[...]
 
// Close the serial port.
port.close();
 
[...]