edu.wpi.first.wpilibj
Class SerialPort

java.lang.Object
  edu.wpi.first.wpilibj.SerialPort

public class SerialPort
extends java.lang.Object

Driver for the RS-232 serial port on the cRIO. The current implementation uses the VISA formatted I/O mode. This means that all traffic goes through the formatted buffers. This allows the intermingled use of print(), readString(), and the raw buffer accessors read() and write(). More information can be found in the NI-VISA User Manual here: http://www.ni.com/pdf/manuals/370423a.pdf and the NI-VISA Programmer's Reference Manual here: http://www.ni.com/pdf/manuals/370132c.pdf

Nested Class Summary

static class	SerialPort.FlowControl Represents what type of flow control to use for serial communication
static class	SerialPort.Parity Represents the parity to use for serial communications
static class	SerialPort.StopBits Represents the number of stop bits to use for Serial Communication
static class	SerialPort.WriteBufferMode Represents which type of buffer mode to use when writing to a serial port

Constructor Summary

SerialPort(int baudRate)
Create an instance of a Serial Port class.

SerialPort(int baudRate, int dataBits)
Create an instance of a Serial Port class.

SerialPort(int baudRate, int dataBits, SerialPort.Parity parity)
Create an instance of a Serial Port class.

SerialPort(int baudRate, int dataBits, SerialPort.Parity parity, SerialPort.StopBits stopBits)
Create an instance of a Serial Port class.

Method Summary

void	disableTermination() Disable termination behavior.
void	enableTermination() Enable termination and specify the termination character.
void	enableTermination(char terminator) Enable termination and specify the termination character.
void	flush() Force the output buffer to be written to the port.
void	free() Destructor.
int	getBytesReceived() Get the number of bytes currently available to read from the serial port.
void	print(java.lang.String write) Deprecated. use write(string.getBytes()) instead
byte[]	read(int count) Read raw bytes out of the buffer.
java.lang.String	readString() Read a string out of the buffer.
java.lang.String	readString(int count) Read a string out of the buffer.
void	reset() Reset the serial port driver to a known state.
void	setFlowControl(SerialPort.FlowControl flowControl) Set the type of flow control to enable on this port.
void	setTimeout(double timeout) Configure the timeout of the serial port.
void	setWriteBufferMode(SerialPort.WriteBufferMode mode) Specify the flushing behavior of the output buffer.
int	write(byte[] buffer, int count) Write raw bytes to the buffer.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SerialPort

public SerialPort(int baudRate,
                  int dataBits,
                  SerialPort.Parity parity,
                  SerialPort.StopBits stopBits)
           throws VisaException

Create an instance of a Serial Port class.

Parameters:

baudRate - The baud rate to configure the serial port. The cRIO-9074 supports up to 230400 Baud.

dataBits - The number of data bits per transfer. Valid values are between 5 and 8 bits.

parity - Select the type of parity checking to use.

stopBits - The number of stop bits to use as defined by the enum StopBits.

Throws:

VisaException

SerialPort

public SerialPort(int baudRate,
                  int dataBits,
                  SerialPort.Parity parity)
           throws VisaException

Create an instance of a Serial Port class. Defaults to one stop bit.

Parameters:

baudRate - The baud rate to configure the serial port. The cRIO-9074 supports up to 230400 Baud.

dataBits - The number of data bits per transfer. Valid values are between 5 and 8 bits.

parity - Select the type of parity checking to use.

Throws:

VisaException

SerialPort

public SerialPort(int baudRate,
                  int dataBits)
           throws VisaException

Create an instance of a Serial Port class. Defaults to no parity and one stop bit.

Parameters:

baudRate - The baud rate to configure the serial port. The cRIO-9074 supports up to 230400 Baud.

dataBits - The number of data bits per transfer. Valid values are between 5 and 8 bits.

Throws:

VisaException

SerialPort

public SerialPort(int baudRate)
           throws VisaException

Create an instance of a Serial Port class. Defaults to 8 databits, no parity, and one stop bit.

Parameters:

baudRate - The baud rate to configure the serial port. The cRIO-9074 supports up to 230400 Baud.

Throws:

VisaException

Method Detail

free

public void free()

Destructor.

setFlowControl

public void setFlowControl(SerialPort.FlowControl flowControl)
                    throws VisaException

Set the type of flow control to enable on this port. By default, flow control is disabled.

Parameters:

flowControl -

Throws:

VisaException

enableTermination

public void enableTermination(char terminator)
                       throws VisaException

Enable termination and specify the termination character. Termination is currently only implemented for receive. When the the terminator is received, the read() or readString() will return fewer bytes than requested, stopping after the terminator.

Parameters:

terminator - The character to use for termination.

Throws:

VisaException

enableTermination

public void enableTermination()
                       throws VisaException

Enable termination and specify the termination character. Termination is currently only implemented for receive. When the the terminator is received, the read() or readString() will return fewer bytes than requested, stopping after the terminator. The default terminator is '\n'

Throws:

VisaException

disableTermination

public void disableTermination()
                        throws VisaException

Disable termination behavior.

Throws:

VisaException

getBytesReceived

public int getBytesReceived()
                     throws VisaException

Get the number of bytes currently available to read from the serial port.

Returns:

The number of bytes available to read.

Throws:

VisaException

print

public void print(java.lang.String write)
           throws VisaException

Deprecated. use write(string.getBytes()) instead

Output formatted text to the serial port.

Parameters:

write - A string to write

Throws:

VisaException

readString

public java.lang.String readString()
                            throws VisaException

Read a string out of the buffer. Reads the entire contents of the buffer

Returns:

The read string

Throws:

VisaException

readString

public java.lang.String readString(int count)
                            throws VisaException

Read a string out of the buffer. Reads the entire contents of the buffer

Parameters:

count - the number of characters to read into the string

Returns:

The read string

Throws:

VisaException

read

public byte[] read(int count)
            throws VisaException

Read raw bytes out of the buffer.

Parameters:

count - The maximum number of bytes to read.

Returns:

An array of the read bytes

Throws:

VisaException

write

public int write(byte[] buffer,
                 int count)
          throws VisaException

Write raw bytes to the buffer.

Parameters:

buffer - the buffer to read the bytes from.

count - The maximum number of bytes to write.

Returns:

The number of bytes actually written into the port.

Throws:

VisaException

setTimeout

public void setTimeout(double timeout)
                throws VisaException

Configure the timeout of the serial port. This defines the timeout for transactions with the hardware. It will affect reads if less bytes are available than the read buffer size (defaults to 1) and very large writes.

Parameters:

timeout - The number of seconds to to wait for I/O.

Throws:

VisaException

setWriteBufferMode

public void setWriteBufferMode(SerialPort.WriteBufferMode mode)
                        throws VisaException

Specify the flushing behavior of the output buffer. When set to kFlushOnAccess, data is synchronously written to the serial port after each call to either print() or write(). When set to kFlushWhenFull, data will only be written to the serial port when the buffer is full or when flush() is called.

Parameters:

mode - The write buffer mode.

Throws:

VisaException

flush

public void flush()
           throws VisaException

Force the output buffer to be written to the port. This is used when setWriteBufferMode() is set to kFlushWhenFull to force a flush before the buffer is full.

Throws:

VisaException

reset

public void reset()
           throws VisaException

Reset the serial port driver to a known state. Empty the transmit and receive buffers in the device and formatted I/O.

Throws:

VisaException