bmp_event.c File Reference

Event handling routines for BMP LPC1768. More...

#include "lpc17xx.h"
#include "bmp.h"

Macros
#define	NUM_EVENTS   16
	Number of events available for use.

Functions
void	event_set_byte (uint32_t addr, uint32_t data)
	Set a byte at an address.
void	event_init (uint32_t priority)
	Initialise the event processing system.
void	proc_queue_add (event_t *e)
	Adds an event to a list of events which can (all) be executed at some later time.
void	proc_queue_run (void)
	Execute a list of events (in the order in which they were added to the list).
void	TIMER3_IRQHandler (void)
	Interrupt handler for the timer which is handling events.
void	event_cancel (event_t *e, uint32_t ID)
	Cancel an event that was previously scheduled.
event_t *	event_new (event_proc proc, uint32_t arg1, uint32_t arg2)
	Allocates a new event.
void	event_schedule (event_t *e, uint32_t time)
	Schedules an event to occur some time in the future.

Variables
static event_t *	event_list
	List of free events.
static event_t *	event_queue
	List of active events.
static event_t *	proc_head
	List of queued "proc" events.
static event_t *	proc_tail
	and tail of that list
static uint32_t	event_id
	Makes unique ID for active events.
static uint32_t	event_count
	Number of events currently in use.
static uint32_t	event_max
	Maximum number ever used.
static event_t	events [NUM_EVENTS]
	Storage for events.

Detailed Description

Event handling routines for BMP LPC1768.

Copyright

© The University of Manchester - 2012-2015

Author

Steve Temple, APT Group, School of Computer Science

Function Documentation

event_set_byte()

void event_set_byte	(	uint32_t	addr,
		uint32_t	data
	)

Set a byte at an address.

Parameters

[in]	addr	The address to write at.
[in]	data	The value to write there.

event_init()

void event_init

(

uint32_t

priority

)

Initialise the event processing system.

Parameters

[in]

priority

Priority to use for the driving timer interrupt

proc_queue_add()

void proc_queue_add

(

event_t *

e

)

Adds an event to a list of events which can (all) be executed at some later time.

The order of execution is the same as that of addition to the list.

Parameters

[in]

e

The event to add.

proc_queue_run()

void proc_queue_run

(

void

)

Execute a list of events (in the order in which they were added to the list).

Events are returned to the free queue after execution.

TIMER3_IRQHandler()

void TIMER3_IRQHandler

(

void

)

Interrupt handler for the timer which is handling events.

Timer 3 interrupt handler.

Events added to the queue while this interrupt is processing will not be processed until the next time this interrupt is called.

event_cancel()

void event_cancel	(	event_t *	e,
		uint32_t	ID
	)

Cancel an event that was previously scheduled.

The ID that was allocated when the event was created must be given in case the event has already executed and possibly been recycled.

It is potentially quite difficult to cancel an event at the head of the event queue so in this case the "proc" is made NULL and the event left to terminate on the timer interrupt.

Parameters

[in]	e	The event to cancel.
[in]	ID	The ID that the event is expected to have.

event_new()

event_t * event_new	(	event_proc	proc,
		uint32_t	arg1,
		uint32_t	arg2
	)

Allocates a new event.

Allocates a new event from the free queue and intialise "proc", "arg1" and "arg2" fields. The "ID", "next" and "time" fields are also set.

Parameters

[in]	proc	The event handler
[in]	arg1	First argument to pass to proc when event fires
[in]	arg2	Second argument to pass to proc when event fires

Returns

The allocated event, or NULL if no event can be allocated

event_schedule()

void event_schedule	(	event_t *	e,
		uint32_t	time
	)

Schedules an event to occur some time in the future.

Parameters

[in]	e	The event to schedule
[in]	time	How many μs in the future to schedule the event firing at