Ab protocol interface

These functions should be called to get the AB protocol up and running. More...

Defines
#define	DEBUG   0
	Set to 1 to get some debugging on LCD, although I do not recommend this.
#define	WRITE_WAIT_TIME   10
#define	WRITE_TIMEOUT   100
Functions
int	init_ab_protocol_8 (void(*u_portHandler)(const unsigned char *message, unsigned char length), unsigned char id)
	Initialises everything needed for use of reliable protocol for short messages (<253 bytes).
int	ab_awrite (const unsigned char *message, unsigned char length, unsigned char destination)
	Use this function to asynchronously send a message.
int	ab_swrite (const unsigned char *message, unsigned char length, unsigned char destination)
	Use this function to synchronously send a message.
int	init_ab_protocol_16 (void(*u_portHandler)(const unsigned char *message, unsigned short length), unsigned char id, unsigned char max_id)
	Initialises everything needed for use of reliable protocol for long messages (<65533 bytes).
int	ab_swrite_16 (const unsigned char *message, unsigned short length, unsigned char destination)
	Use this function to synchronously send a long message.
Variables
unsigned char	ab_source
	In your porthandler, you can use this variable to know from where the message comes.

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Detailed Description

These functions should be called to get the AB protocol up and running.

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Define Documentation

#define WRITE_TIMEOUT   100

Defines (in ticks) the waiting time for a retransmission to a certain site which did not send any acks Timeout is calculated as follows : WRITE_TIMEOUT + (random between 0 and WRITE_TIMEOUT) Definition at line 153 of file ab.h.

#define WRITE_WAIT_TIME   10

Defines (in ticks) the waiting time for each loop in the send thread A message to a site will AT MOST be delayed with this time before it will be sent (of course, this is an estimate, since we are not running on a realtime OS, and threading may affect these values) Definition at line 148 of file ab.h.

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Function Documentation

int ab_awrite (  const unsigned char *  message, unsigned char  length, unsigned char  destination )

Use this function to asynchronously send a message. The message is added to the list and will be sent as soon as possible. The function returns immediately Parameters: message  The message to send length  The length of the message destination  The destination for the message Returns: 0 on success, 1 otherwise Definition at line 410 of file ab.c.

int ab_swrite (  const unsigned char *  message, unsigned char  length, unsigned char  destination )

Use this function to synchronously send a message. The message is added to the list and will be sent as soon as possible. The function returns when an acknowledgment is received for the message Parameters: message  The message to send length  The length of the message destination  The destination for the message Returns: 0 on success, 1 otherwise Definition at line 425 of file ab.c.

int ab_swrite_16 (  const unsigned char *  message, unsigned short  length, unsigned char  destination )

Use this function to synchronously send a long message. The message is added to the list and will be sent as soon as possible. The function returns when an acknowledgment is received for the message Parameters: message  The message to send length  The length of the message destination  The destination for the message Returns: number of bytes sent, 0 on error Remarks: Can only be used in conjunction with init_ab_protocol_16. (In fact this function is built on top of init_ab_protocol_8, so you should definitely not use any other sending function)

int init_ab_protocol_16 (  void(*  u_portHandler)(const unsigned char *message, unsigned short length), unsigned char  id, unsigned char  max_id )

Initialises everything needed for use of reliable protocol for long messages (<65533 bytes). Parameters: u_portHandler  The function that will be called when a message is received. Since large messages may cause insufficient memory, a message NULL will be sent to the user when such an error occurs. In that case the message is lost. id  The id of the current site max_id  The highest id in the system Returns: 0 on success 1, otherwise (memory allocation problems) Remarks: Can only be used with the function ab_swrite_16 A future release may take care of the NULL messages sent to the user in case of memory allocation problems, by not accepting the message, so that the sender must resend its message until enough memory is freed. For the moment, this is not the case, and the sender thinks that the message is handled correctely.

int init_ab_protocol_8 (  void(*  u_portHandler)(const unsigned char *message, unsigned char length), unsigned char  id )

Initialises everything needed for use of reliable protocol for short messages (<253 bytes). Parameters: u_portHandler  The function that will be called when a message is received id  The id of the current site Returns: 0 on success Definition at line 353 of file ab.c.

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