embeddedlibrary
reusable software modules for embedded systems
Macros | Functions
Event Triggered Task Module
Task Management Module

Macros

#define MAX_EVENTS   2
 max number of events that can be registered
 

Functions

void Event_Init ()
 
void Event_Tick ()
 
void Event_Register (uint8_t *flag, void(*fn_ptr)(void))
 
void Event_Unregister (void(*fn)(void))
 

Detailed Description

The Event Module is intended to be used with interrupts when a task needs to run in response to the interrupt and the desire is to not call any tasks from the interrupts. This module makes this easy by allowing the user to register a task to run (see Event_Register()) in response to a flag being set to a non zero value.

Todo:
Josh Hass Add a code example (when done change this line to "@todo MM check <your names> documentation"

Function Documentation

void Event_Init ( )
Warning
JaH 9/10

Initializes list of events (sets size to 0)

void Event_Register ( uint8_t *  flag,
void(*)(void)  fn_ptr 
)

Event Register will add an event (a function pointer) to the events array

If the array is not full (size < MAX_EVENTS), then a new event will be added at the end of the array, where the flag and the function pointer are passed in as parameters.

Event_Init() must be used to initialize the events array prior to calling Event_Register or Event_Unregister

Parameters
flagboolean flag to indicate if the event function pointer for the corresponding function pointer should be called upon a sequential Event_Tick() call
fn_ptrfunction pointer to be called when Event_Tick() is called and the corresponding event in the global events array has a set flag value of 1.
Note
the .c file for this has "fn" as the parameter name, not "fn_ptr"
Warning
LH 10/10
void Event_Tick ( )
Todo:
Austin H. Document this function (when done change this line to "@todo MM check <your names> documentation"
void Event_Unregister ( void(*)(void)  fn)

Event_Unregister unregisters an event from the list of events that are to occur. This is done by passing a function pointer that points to the function that needs to be unregistered. Event_Unregister then loops through the event array to find the matching function pointer. When the function pointer is found the remaining items in the event array are shifted left to overwrite the function pointer.

Parameters
fnis a function pointer pointing to the function to unregister.
Warning
EJ 10/10