User API

Functions of the SLIP interface. More...

Functions
netStatus	netSLIP_Listen (void)
	Start SLIP interface to accept incoming SLIP connections. [thread-safe].
netStatus	netSLIP_Connect (const char *dial_num)
	Start a dial-up connection to remote SLIP server. [thread-safe].
netStatus	netSLIP_Close (void)
	Disconnect SLIP link between two modems. [thread-safe].
bool	netSLIP_LinkUp (void)
	Determine the state of SLIP link. [thread-safe].

Description

Functions of the SLIP interface.

To start a dial-up connection to a remote SLIP server, use netSLIP_Connect (client mode). If you want to wait for an incoming connection, use netSLIP_Listen instead (server mode). To check the link status, use netSLIP_LinkUp. This can be done in client and server mode and can be used to continuously monitor the SLIP link. To disconnect the SLIP link, use netSLIP_Close (for client and server mode). Usually, this is done by the client. Note that the netSLIP_Close function does not change the running mode of the SLIP daemon. If the SLIP daemon was in server mode, SLIP daemon re-initializes the modem driver to accept further incoming calls.

Function Documentation

netSLIP_Close()

netStatus netSLIP_Close

(

void

)

Disconnect SLIP link between two modems. [thread-safe].

Returns

status code that indicates the execution status of the function.

The function netSLIP_Close disconnects the SLIP link between the two modems.

Possible netStatus return values:

• netOK: Disconnection started.

Note

• You can call the netSLIP_Close function when the SLIP network daemon is either in client mode or in server mode.
• Since the SLIP client starts a dial-up connection, it is also the SLIP client that usually disconnects the SLIP link.
• The netSLIP_Close function does not change the running mode of the SLIP daemon. If the SLIP daemon was in server mode, SLIP daemon re-initializes the modem driver to accept further incoming calls.

Code Example

void disconnect_link (void) {
  // Disconnect a dial-up link. 
  netSLIP_Close ();
}

netSLIP_Connect()

netStatus netSLIP_Connect

(

const char *

dial_num

)

Start a dial-up connection to remote SLIP server. [thread-safe].

Parameters

[in]

dial_num

phone number of remote SLIP server.

Returns

status code that indicates the execution status of the function.

The function netSLIP_Connect starts a dial-up connection to the remote SLIP server by starting the SLIP daemon in client mode.

The argument dial_num points to a null-terminated string containing the phone number of the remote SLIP server.

Possible netStatus return values:

• netOK: Dial-up connection started.
• netInvalidParameter: Invalid dial_num parameter provided.
• netWrongState: Dial-up connection already established.

Note

• You must call the netSLIP_Connect function when you want to establish a dial-up connection using SLIP.
• When using a direct cable connection, you can set dial_num to NULL because the Null_Modem device driver ignores dial_num.

Code Example

void dial_remote (void) {
  // Dial remote SLIP Server. 
  netSLIP_Connect ("04213372");
}

netSLIP_LinkUp()

bool netSLIP_LinkUp

(

void

)

Determine the state of SLIP link. [thread-safe].

Returns

link state:

• true = Link is up, IP frames can be exchanged.
• false = Link is down.

The function netSLIP_LinkUp determines the state of SLIP link between the two modems. It returns true if IP frames can be exchanged over the SLIP link.

Note

• You can call the netSLIP_LinkUp function when the SLIP network daemon is either in client mode or in server mode.
• You can also use the netSLIP_LinkUp function to continuously monitor the state of the SLIP link.

Code Example

void connect_soc (void) {
  // Connect TCP socket when SLIP is up. 
  if(netSLIP_LinkUp()) {
    netTCP_Connect (socket_tcp, remip, 1000, 0);
  }
}

netSLIP_Listen()

netStatus netSLIP_Listen

(

void

)

Start SLIP interface to accept incoming SLIP connections. [thread-safe].

Returns

status code that indicates the execution status of the function.

The function netSLIP_Listen configures the SLIP interface to accept incoming SLIP connections by starting the SLIP daemon in server mode.

Note

It is common to call netSLIP_Listen at system start-up.

Possible netStatus return values:

• netOK: Listening to inbound dial-up connections started.
• netWrongState: Dial-up connection already established.

Code Example

int main (void) {
  netInitialize ();
  // Activate the SLIP interface. 
  netSLIP_Listen ();
   ..
}