Real-time Timer (RTT)

Functions
void	rtt_disable_interrupt (Rtt *p_rtt, uint32_t ul_sources)
	Disable RTT interrupts. More...
void	rtt_enable_interrupt (Rtt *p_rtt, uint32_t ul_sources)
	Enable RTT interrupts. More...
uint32_t	rtt_get_status (Rtt *p_rtt)
	Get the status register value of the given RTT. More...
uint32_t	rtt_init (Rtt *p_rtt, uint16_t us_prescaler)
	Initialize the given RTT. More...
uint32_t	rtt_read_timer_value (Rtt *p_rtt)
	Read the current value of the RTT timer value. More...
uint32_t	rtt_write_alarm_time (Rtt *p_rtt, uint32_t ul_alarm_time)
	Configure the RTT to generate an alarm at the given time. alarm happens when CRTV value equals ALMV+1, so RTT_AR should be alarmtime - 1. if you want to get alarm when rtt hit 0 , ALMV should be set to 0xFFFFFFFF. More...

Detailed Description

The Real-time Timer is built around a 32-bit counter used to count roll-over events of the programmable 16-bit prescaler, which enables counting elapsed seconds from a 32 kHz slow clock source. This is a driver for configuration and use of the RTT peripheral.

Function Documentation

rtt_disable_interrupt()

void rtt_disable_interrupt	(	Rtt *	p_rtt,
		uint32_t	ul_sources
	)

Disable RTT interrupts.

Parameters

p_rtt	Pointer to an RTT instance.
ul_sources	Interrupts to be disabled.

Definition at line 175 of file rtt.c.

rtt_enable_interrupt()

void rtt_enable_interrupt	(	Rtt *	p_rtt,
		uint32_t	ul_sources
	)

Enable RTT interrupts.

Parameters

p_rtt	Pointer to an RTT instance.
ul_sources	Interrupts to be enabled.

Definition at line 157 of file rtt.c.

rtt_get_status()

uint32_t rtt_get_status

(

Rtt *

p_rtt

)

Get the status register value of the given RTT.

Parameters

p_rtt

Pointer to an RTT instance.

Returns

The Real-time Timer status.

Definition at line 212 of file rtt.c.

rtt_init()

uint32_t rtt_init	(	Rtt *	p_rtt,
		uint16_t	us_prescaler
	)

Initialize the given RTT.

Note

This function restarts the real-time timer. If w_prescaler is equal to zero, the prescaler period is equal to 2^16 * SCLK period. If not, the prescaler period is equal to us_prescaler * SCLK period.

Parameters

p_rtt	Pointer to an RTT instance.
us_prescaler	Prescaler value for the RTT.

Returns

0 if successful.

Definition at line 78 of file rtt.c.

rtt_read_timer_value()

uint32_t rtt_read_timer_value

(

Rtt *

p_rtt

)

Read the current value of the RTT timer value.

Parameters

p_rtt

Pointer to an RTT instance.

Returns

The current Real-time Timer value.

Definition at line 194 of file rtt.c.

rtt_write_alarm_time()

uint32_t rtt_write_alarm_time	(	Rtt *	p_rtt,
		uint32_t	ul_alarm_time
	)

Configure the RTT to generate an alarm at the given time. alarm happens when CRTV value equals ALMV+1, so RTT_AR should be alarmtime - 1. if you want to get alarm when rtt hit 0 , ALMV should be set to 0xFFFFFFFF.

Parameters

p_rtt	Pointer to an RTT instance.
ul_alarm_time	Alarm time,Alarm time = ALMV + 1.

Return values

0	Configuration is done.

Alarm time = ALMV + 1,If the incoming parameter is 0, the ALMV is set to 0xFFFFFFFF.

Definition at line 227 of file rtt.c.