Software buffers and interrupt driven tx and rx for Serial. More...

#include <BufferedSerial.h>

Inheritance diagram for BufferedSerial:

Public Member Functions
	BufferedSerial (PinName tx, PinName rx, uint32_t buf_size=256, uint32_t tx_multiple=4, const char *name=NULL)

virtual int	getc (void)

virtual int	printf (const char *format,...)

virtual int	putc (int c)

virtual int	puts (const char *s)

virtual int	readable (void)

virtual ssize_t	write (const void *s, std::size_t length)

virtual int	writeable (void)

virtual	~BufferedSerial (void)

Private Member Functions
void	prime (void)

void	rxIrq (void)

void	txIrq (void)

Private Attributes
uint32_t	_buf_size

Buffer< char >	_rxbuf

uint32_t	_tx_multiple

Buffer< char >	_txbuf

Detailed Description

Software buffers and interrupt driven tx and rx for Serial.

A serial port (UART) for communication with other serial devices

Can be used for Full Duplex communication, or Simplex by specifying one pin as NC (Not Connected)

Example:

#include "mbed.h"
#include "BufferedSerial.h"
BufferedSerial pc(USBTX, USBRX);
int main()
{ 
    while(1)
    {
        Timer s;
      
        s.start();
        pc.printf("Hello World - buffered\n");
        int buffered_time = s.read_us();
        wait(0.1f); // give time for the buffer to empty
      
        s.reset();
        printf("Hello World - blocking\n");
        int polled_time = s.read_us();
        s.stop();
        wait(0.1f); // give time for the buffer to empty
      
        pc.printf("printf buffered took %d us\n", buffered_time);
        pc.printf("printf blocking took %d us\n", polled_time);
        wait(0.5f);
    }
}

Definition at line 71 of file BufferedSerial.h.

Constructor & Destructor Documentation

BufferedSerial::BufferedSerial	(	PinName	tx,
		PinName	rx,
		uint32_t	buf_size = `256`,
		uint32_t	tx_multiple = `4`,
		const char *	name = `NULL`
	)

Create a BufferedSerial port, connected to the specified transmit and receive pins

Parameters

tx	Transmit pin
rx	Receive pin
buf_size	printf() buffer size
tx_multiple	amount of max printf() present in the internal ring buffer at one time
name	optional name

Note: Either tx or rx may be specified as NC if unused

Definition at line 26 of file BufferedSerial.cpp.

BufferedSerial::~BufferedSerial ( void )

virtual

Destroy a BufferedSerial port

Definition at line 35 of file BufferedSerial.cpp.

Member Function Documentation

int BufferedSerial::getc ( void )

virtual

Get a single byte from the BufferedSerial Port. Should check readable() before calling this.

Returns: A byte that came in on the Serial Port

Definition at line 53 of file BufferedSerial.cpp.

void BufferedSerial::prime ( void )

private

Definition at line 146 of file BufferedSerial.cpp.

int BufferedSerial::printf	(	const char *	format,
			...
	)

virtual

Write a formatted string to the BufferedSerial Port.

Parameters

format The string + format specifiers to write to the Serial Port

Returns: The number of bytes written to the Serial Port Buffer

Definition at line 82 of file BufferedSerial.cpp.

int BufferedSerial::putc ( int c )

virtual

Write a single byte to the BufferedSerial Port.

Parameters

c	The byte to write to the Serial Port

Returns: The byte that was written to the Serial Port Buffer

Definition at line 58 of file BufferedSerial.cpp.

int BufferedSerial::puts ( const char * s )

virtual

Write a string to the BufferedSerial Port. Must be NULL terminated

Parameters

s	The string to write to the Serial Port

Returns: The number of bytes written to the Serial Port Buffer

Definition at line 66 of file BufferedSerial.cpp.

int BufferedSerial::readable ( void )

virtual

Check on how many bytes are in the rx buffer

Returns: 1 if something exists, 0 otherwise

Definition at line 43 of file BufferedSerial.cpp.

void BufferedSerial::rxIrq ( void )

private

Definition at line 120 of file BufferedSerial.cpp.

void BufferedSerial::txIrq ( void )

private

Definition at line 130 of file BufferedSerial.cpp.

ssize_t BufferedSerial::write	(	const void *	s,
		std::size_t	length
	)

virtual

Write data to the Buffered Serial Port

Parameters

s	A pointer to data to send
length	The amount of data being pointed to

Returns: The number of bytes written to the Serial Port Buffer

Definition at line 103 of file BufferedSerial.cpp.

int BufferedSerial::writeable ( void )

virtual

Check to see if the tx buffer has room

Returns: 1 always has room and can overwrite previous content if too small / slow

Definition at line 48 of file BufferedSerial.cpp.

Member Data Documentation

uint32_t BufferedSerial::_buf_size

private

Definition at line 76 of file BufferedSerial.h.

Buffer<char> BufferedSerial::_rxbuf

private

Definition at line 74 of file BufferedSerial.h.

uint32_t BufferedSerial::_tx_multiple

private

Definition at line 77 of file BufferedSerial.h.

Buffer<char> BufferedSerial::_txbuf

private

Definition at line 75 of file BufferedSerial.h.

The documentation for this class was generated from the following files:

Public Member Functions

Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation