include/c/urg_connection.h File Reference

Process communications. More...

#include "urg_serial.h"
#include "urg_tcpclient.h"

Go to the source code of this file.

Data Structures
struct	urg_connection_t
	Connection resources. More...
Enumerations
enum	{ URG_CONNECTION_TIMEOUT = -1 }
	Defines constants. More...
enum	urg_connection_type_t { URG_SERIAL, URG_ETHERNET }
	Connection type. More...
Functions
int	connection_open (urg_connection_t *connection, urg_connection_type_t connection_type, const char *device, long baudrate_or_port)
	Connection.
void	connection_close (urg_connection_t *connection)
	Disconnection.
int	connection_set_baudrate (urg_connection_t *connection, long baudrate)
	Configures the baudrate.
int	connection_write (urg_connection_t *connection, const char *data, int size)
	Send.
int	connection_read (urg_connection_t *connection, char *data, int max_size, int timeout)
	Receive.
int	connection_readline (urg_connection_t *connection, char *data, int max_size, int timeout)
	Receive until end-of-line.

---

Detailed Description

Process communications.

Author:

Satofumi KAMIMURA

Id:

urg_connection.h,v e5d1719877a2 2015/05/07 04:12:14 jun

---

Enumeration Type Documentation

anonymous enum

Defines constants.

Enumerator:

URG_CONNECTION_TIMEOUT

Return value in case of timeout.

enum urg_connection_type_t

Connection type.

Enumerator:

URG_SERIAL	Serial/USB connection.
URG_ETHERNET	Ethernet connection.

---

Function Documentation

void connection_close

(

urg_connection_t *

connection

)

Disconnection.

Closes the connection with the device

Parameters:

[in,out]

connection

Connection resource

  connection_close(&connection); 

See also:

connection_open()

int connection_open	(	urg_connection_t *	connection,
		urg_connection_type_t	connection_type,
		const char *	device,
		long	baudrate_or_port
	)

Connection.

Connects to the specified device

Parameters:

[in,out]	connection	Connection resource
[in]	connection_type	Connection type
[in]	device	Device name
[in]	baudrate_or_port	Baudrate or port number

Return values:

0	Success
<0	Error

The connection_type is either of:

• URG_SERIAL ... Serial connection
  • URG_ETHERNET .. Ethernet connection

device and baudrate_or_port arguments are defined according to connection_type For example, in case of serial connection:

Example

  connection_t connection;
  if (! connection_open(&connection, URG_SERIAL, "COM1", 115200)) {
      return 1;
  } 

And, in case of ethernet connection:

Example

  connection_t connection;
  if (! connection_open(&connection, URG_ETHERNET, "192.168.0.10", 10940)) {
      return 1;
  } 

See also:

connection_close()

int connection_read	(	urg_connection_t *	connection,
		char *	data,
		int	max_size,
		int	timeout
	)

Receive.

Reads data from the communication channel

Parameters:

[in,out]	connection	Connection resource
[in]	data	Buffer to store received data
[in]	max_size	Maximum size of the buffer
[in]	timeout	Timeout [msec]

Return values:

>=0	Number of bytes received
<0	Error

If timeout argument is negative then the function waits until some data is received

In case no data is received URG_CONNECTION_TIMEOUT is returned.

Example

enum {
    BUFFER_SIZE = 256,
    TIMEOUT_MSEC = 1000,
};
char buffer[BUFFER_SIZE];
n = connection_read(&connection, buffer, BUFFER_SIZE, TIMEOUT_MSEC); 

See also:

connection_write(), connection_readline()

int connection_readline	(	urg_connection_t *	connection,
		char *	data,
		int	max_size,
		int	timeout
	)

Receive until end-of-line.

Reads data until the end-of-line character is detected.

Parameters:

[in,out]	connection	Connection resource
[in]	data	Buffer to store received data
[in]	max_size	Maximum size of the buffer
[in]	timeout	Timeout [msec]

Return values:

>=0	Number of bytes received
<0	Error

If timeout argument is negative then the function waits until some data is received

The null terminator character '\0' is used at the end of data so that the number of bytes does not exceed max_size. This is, the maximum number of received characters is max_size - 1.

The end-of-line character is either '\r' or '\n'

In case no end-of-line is received then returns 0, if no data is received URG_CONNECTION_TIMEOUT is returned.

See also:

connection_write(), connection_read()

int connection_write	(	urg_connection_t *	connection,
		const char *	data,
		int	size
	)

Send.

Writes data over the communication channel

Parameters:

[in,out]	connection	Connection resource
[in]	data	Data to send
[in]	size	Number of bytes to send

Return values:

>=0	Number of bytes sent
<0	Error

Example

  n = connection_write(&connection, "QT\n", 3); 

See also:

connection_read(), connection_readline()