Macros
#define	ZB_MAX_TIME_VAL ZB_UINT32_MAX

#define	ZB_MIN_TIME_VAL ZB_UINT32_MIN

#define	ZB_HALF_MAX_TIME_VAL (ZB_MAX_TIME_VAL / 2)

#define	ZB_TIMER_GET() (zb_timer_get())

#define	ZB_TIME_SUBTRACT(a, b) ((zb_time_t)((a) - (b)) < ZB_HALF_MAX_TIME_VAL ? (zb_time_t)((a) - (b)) : (zb_time_t)((b) - (a)))

#define	ZB_TIME_ADD(a, b) (zb_time_t)((a) + (b))

#define	ZB_TIME_GE(a, b) ((zb_time_t)((a) - (b)) < ZB_HALF_MAX_TIME_VAL)

#define	ZB_TIME_ONE_SECOND ZB_MILLISECONDS_TO_BEACON_INTERVAL(1000)

#define	ZB_MILLISECONDS_TO_BEACON_INTERVAL(ms) (((zb_time_t)(ms) * 1000) / ZB_BEACON_INTERVAL_USEC)

#define	ZB_BEACON_INTERVAL_USEC (ZB_SYMBOL_DURATION_USEC * ZB_ABASE_SUPERFRAME_DURATION)

#define	ZB_TIME_BEACON_INTERVAL_TO_MSEC(t) ((ZB_BEACON_INTERVAL_USEC * (zb_time_t)(t)) / 1000)

#define	ZB_TIME_BEACON_INTERVAL_TO_USEC(t) ((zb_uint64_t)ZB_BEACON_INTERVAL_USEC * (t))

#define	ZB_TIME_QUARTERECONDS(n) (ZB_TIME_BEACON_INTERVAL_TO_MSEC((n)) / 250)

#define	ZB_QUARTERECONDS_TO_MSEC(n) 250*(n)

#define	ZB_QUARTERECONDS_TO_BEACON_INTERVAL(qsec) ZB_MILLISECONDS_TO_BEACON_INTERVAL(250*qsec)

#define	ZB_SECONDS_TO_MILLISECONDS(_s) (1000l*(_s))

#define	ZB_MILLISECONDS_TO_USEC(ms) ((ms) * (1000))

#define	ZB_USECS_TO_MILLISECONDS(usec) ((usec) / (1000))

Typedefs
typedef zb_uint32_t	zb_time_t

Detailed Description

ZBOSS time subsystem is based on hardware timer. There is a special zb_time_t type defined in ZBOSS API for working with time variables in ZBOSS framework. The zb_time_t type size may be limited depending on a platform. ZBOSS handles the overflow.

The basic time measurement unit is "beacon interval" (tick) equal to 15.36 microseconds (see Zigbee specification revision 22 section 3.6.4.1 Scheduling Method).

Macro Definition Documentation

◆ ZB_BEACON_INTERVAL_USEC

#define ZB_BEACON_INTERVAL_USEC (ZB_SYMBOL_DURATION_USEC * ZB_ABASE_SUPERFRAME_DURATION)

Beacon interval in microseconds

1 beacon interval = aBaseSuperframeDuration * symbol duration

1 symbol = 16e-6 sec (mac spec 6.5.3.2 Symbol rate) for 2.4GHz ZB. 1 beacon interval = 15.360 ms.

◆ ZB_HALF_MAX_TIME_VAL

#define ZB_HALF_MAX_TIME_VAL (ZB_MAX_TIME_VAL / 2)

A half of defined maximum timer value.

◆ ZB_MAX_TIME_VAL

#define ZB_MAX_TIME_VAL ZB_UINT32_MAX

Maximum timer value, if 32-bit timer is used.

◆ ZB_MILLISECONDS_TO_BEACON_INTERVAL

#define ZB_MILLISECONDS_TO_BEACON_INTERVAL ( ms ) (((zb_time_t)(ms) * 1000) / ZB_BEACON_INTERVAL_USEC)

Convert time from milliseconds to beacon intervals (32-bit platforms).

◆ ZB_MILLISECONDS_TO_USEC

#define ZB_MILLISECONDS_TO_USEC ( ms ) ((ms) * (1000))

Convert from milliseconds to microseconds

◆ ZB_MIN_TIME_VAL

#define ZB_MIN_TIME_VAL ZB_UINT32_MIN

Minimum timer value, if 32-bit timer is used.

◆ ZB_QUARTERECONDS_TO_BEACON_INTERVAL

#define ZB_QUARTERECONDS_TO_BEACON_INTERVAL ( qsec ) ZB_MILLISECONDS_TO_BEACON_INTERVAL(250*qsec)

Convert from quarterseconds to beacon

◆ ZB_QUARTERECONDS_TO_MSEC

#define ZB_QUARTERECONDS_TO_MSEC ( n ) 250*(n)

Convert from quarterseconds to msec

◆ ZB_SECONDS_TO_MILLISECONDS

#define ZB_SECONDS_TO_MILLISECONDS ( _s ) (1000l*(_s))

Convert from seconds to milliseconds

◆ ZB_TIME_ADD

#define ZB_TIME_ADD	(	a,
		b
	)	(zb_time_t)((a) + (b))

Time add: add 'a' to 'b'

Overflow is possible, but this is ok - it handled by subtraction and compare macros.

Parameters

a	- time to add to
b	- value to add

Returns: addition result

◆ ZB_TIME_BEACON_INTERVAL_TO_MSEC

#define ZB_TIME_BEACON_INTERVAL_TO_MSEC ( t ) ((ZB_BEACON_INTERVAL_USEC * (zb_time_t)(t)) / 1000)

Convert time from beacon intervals to milliseconds (32-bit platform).

◆ ZB_TIME_BEACON_INTERVAL_TO_USEC

#define ZB_TIME_BEACON_INTERVAL_TO_USEC ( t ) ((zb_uint64_t)ZB_BEACON_INTERVAL_USEC * (t))

Convert time from beacon intervals to microseconds

◆ ZB_TIME_GE

#define ZB_TIME_GE	(	a,
		b
	)	((zb_time_t)((a) - (b)) < ZB_HALF_MAX_TIME_VAL)

Compare times a and b - check that a >= b

Taking into account overflow and unsigned values arithmetic and supposing difference between a and b can't be > 1/2 of the overall time values diapason, a >= b only if a - b < values_diapason/2

Parameters

a	- first time value to compare
b	- second time value to compare

Returns: 1 is a >= b, 0 otherwise

◆ ZB_TIME_ONE_SECOND

#define ZB_TIME_ONE_SECOND ZB_MILLISECONDS_TO_BEACON_INTERVAL(1000)

One second timeout

◆ ZB_TIME_QUARTERECONDS

#define ZB_TIME_QUARTERECONDS ( n ) (ZB_TIME_BEACON_INTERVAL_TO_MSEC((n)) / 250)

Quarterseconds timeout

◆ ZB_TIME_SUBTRACT

#define ZB_TIME_SUBTRACT	(	a,
		b
	)	((zb_time_t)((a) - (b)) < ZB_HALF_MAX_TIME_VAL ? (zb_time_t)((a) - (b)) : (zb_time_t)((b) - (a)))

Time subtraction: subtract 'b' from 'a'

Take overflow into account: change sign (subtraction order) if result > values_diapason/2. Suppose a always >= b, so result is never negative. This macro will be used to calculate, for example, amount of time to sleep

it is positive by definition. Do not use it to compare time values! Use ZB_TIME_GE() instead.
Note
Both a and b is of type zb_time_t. Can't decrease time (subtract constant from it) using this macro.

Parameters

a - time to subtract from

b - time to subtract

Returns
subtraction result

◆ ZB_TIMER_GET

#define ZB_TIMER_GET ( ) (zb_timer_get())

Returns: Get current timer value (beacon intervals)

◆ ZB_USECS_TO_MILLISECONDS

#define ZB_USECS_TO_MILLISECONDS ( usec ) ((usec) / (1000))

Convert from microseconds to milliseconds

Typedef Documentation

◆ zb_time_t

typedef zb_uint32_t zb_time_t

Timer functionality.

The idea is: platform has some timer which can be stopped or run. When run, it increments (or decrements - depends on platform) some counter until counter overflow (underflow), then issues interrupt - wakeups main loop if it sleeping. Time stored in ticks; time resolution is platform dependent, its usual value is 15.36 usec - 1 beacon interval.

Note: Time type has limited capacity (usually 16 bits) and can overflow. Macros which works with time handles overflow. It is supposed that time values will not differ to more then 1/2 of the maximum time value.

All that timer macros will not be used directly by the application code - it is scheduler internals. The only API for timer is ZB_SCHEDULE_ALARM() call. Timer type.

Macros

Typedefs