satnogs::comms::time Class Reference

Time and position information. More...

#include <time.hpp>

Classes
class	to_string_exception

Public Types
enum class	time_src : uint8_t { GNSS_ASSISTED_RTC = 0 , GNSS_ONLY , UPTIME }
	Source of the reported time. More...
enum class	time_granularity {   YEAR , MONTH , DAY , HOUR ,   MIN , SEC }
	Granularity of time represented as string. More...

Public Member Functions
	time (time const &)=delete
void	operator= (time const &)=delete
void	gnss_data_cb (const struct device *dev, const struct gnss_data *data)
time_src	get (uint64_t &t)
	Gets the time in ms.
time_src	get (struct tm &t)
	Gets the current time.
void	set (const struct tm &t)
	Sets the RTC time.
void	gnss (struct gnss_data &data)
	Retrieve latest GNSS information.
uint64_t	uptime ()
	Gets the current system uptime in milliseconds.
uint64_t	last_gnss_update_uptime ()
	Gets the system uptime (in milliseconds) at the time of the last GNSS fix.
uint64_t	last_nmea_update_uptime ()
size_t	to_string (const struct tm &tm, etl::istring &s, time::time_granularity granularity) const
	Return the string represantation of a struct tm time instance following the ISO-8601 paradigm. If the conversion fails, the function returns an empty string.
size_t	to_string (const struct tm &tm, etl::istring &s) const
	Overloading function of time::to_string defaulting to DAY granularity.

Static Public Member Functions
static time &	get_instance ()

Static Public Attributes
static constexpr size_t	to_string_max_size = 20

Detailed Description

Time and position information.

This class provides time and position (if available) information. The SatNOGS-COMMS supports diffent sources of time depending on the configuration and the available peripherals. If the RTC battery is present and has enough voltage, the RTC time is retrieved, if the RTC clock has been set at least once. This can be done either by a telecommand or by the second available time source which is the GNSS. This class uses internally the GNSS modem of the Zephyr-RTOS and parses the NMEA messages that are published on one of the available UART ports. If the GNSS declares a valid fix, the announced time is automatically set to the RTC too.

If the RTC battery is not present or failed mid-flight but the GNSS time is available, the time is updated based on the last known time information from the GNSS and the uptime.

If all the above time sources failed to provide time information, the uptime is used as a last resort.

Definition at line 59 of file time.hpp.

Member Enumeration Documentation

time_granularity

enum class satnogs::comms::time::time_granularity

strong

Granularity of time represented as string.

Enumerator
YEAR
MONTH
DAY
HOUR
MIN
SEC

Definition at line 89 of file time.hpp.

time_src

enum class satnogs::comms::time::time_src : uint8_t

strong

Source of the reported time.

Enumerator
GNSS_ASSISTED_RTC	RTC that may assisted by GNSS. This time source is valid, if the RTC is present and has been set either by a telecommand or by the GNSS
GNSS_ONLY	No RTC installed, but there is time information from a GNSS fix.
UPTIME	No RTC or GNSS time source. The uptime is used to track time.

Definition at line 73 of file time.hpp.

Constructor & Destructor Documentation

time()

satnogs::comms::time::time ( time const & )

delete

Member Function Documentation

get() [1/2]

time::time_src satnogs::comms::time::get

(

struct tm &

t

)

Gets the current time.

See also

time::get(uint64_t &t) for more details

Parameters

t	reference to hold the result

Returns

time::time_src the time source for the time retrieved

Definition at line 152 of file time.cpp.

get() [2/2]

time::time_src satnogs::comms::time::get

(

uint64_t &

t

)

Gets the time in ms.

The current time depends on the time source and it is equal to:

• ms since Linux epoch: In case the time source is time_src::GNSS_ASSISTED_RTC or time_src::GNSS_ONLY
• ms since board power up: In case the time source is time_src::UPTIME

Parameters

t	reference to hold the result

Returns

time::time_src the time source for the time retrieved

Definition at line 111 of file time.cpp.

get_instance()

time & satnogs::comms::time::get_instance ( )

inlinestatic

Definition at line 63 of file time.hpp.

gnss()

void satnogs::comms::time::gnss

(

struct gnss_data &

data

)

Retrieve latest GNSS information.

Parameters

data	reference to store the retrieved information

Definition at line 237 of file time.cpp.

gnss_data_cb()

void satnogs::comms::time::gnss_data_cb	(	const struct device *	dev,
		const struct gnss_data *	data )

Definition at line 54 of file time.cpp.

last_gnss_update_uptime()

uint64_t satnogs::comms::time::last_gnss_update_uptime

(

)

Gets the system uptime (in milliseconds) at the time of the last GNSS fix.

Returns

uint64_t Uptime in milliseconds at the time of the last GNSS update

Definition at line 179 of file time.cpp.

last_nmea_update_uptime()

uint64_t satnogs::comms::time::last_nmea_update_uptime

(

)

Definition at line 185 of file time.cpp.

operator=()

void satnogs::comms::time::operator= ( time const & )

delete

set()

void satnogs::comms::time::set

(

const struct tm &

t

)

Sets the RTC time.

Note

Even if the RTC battery is not present, the RTC subsystem is active while the board is powered-up. Therefore its can be used to accurately track the time

Parameters

t	time in UTC

Definition at line 200 of file time.cpp.

to_string() [1/2]

size_t satnogs::comms::time::to_string	(	const struct tm &	tm,
		etl::istring &	s ) const

Overloading function of time::to_string defaulting to DAY granularity.

Definition at line 326 of file time.cpp.

to_string() [2/2]

size_t satnogs::comms::time::to_string	(	const struct tm &	tm,
		etl::istring &	s,
		time::time_granularity	granularity ) const

Return the string represantation of a struct tm time instance following the ISO-8601 paradigm. If the conversion fails, the function returns an empty string.

Parameters

tm	reference to struct tm that holds the time information
s	etl::string to write to
granularity	specifies the wanted granularity of our stringified time (year, month, day etc.)

Returns

the number of bytes the strftime managed to write

Definition at line 290 of file time.cpp.

uptime()

uint64_t satnogs::comms::time::uptime

(

)

Gets the current system uptime in milliseconds.

Returns

uint64_t The current uptime in milliseconds

Definition at line 167 of file time.cpp.

Member Data Documentation

to_string_max_size

size_t satnogs::comms::time::to_string_max_size = 20

staticconstexpr

Definition at line 84 of file time.hpp.

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The documentation for this class was generated from the following files:

• src/time.hpp
• src/time.cpp