esp-idf/components/esp_system
morris 3a530e3311 Merge branch 'refactor/timer_ll_hal_clean_before_ng' into 'master'
timer: clean up hal/ll for driver-ng

See merge request espressif/esp-idf!15123
2021-10-20 23:59:30 +00:00
..
include WDT: Add support for XTAL32K Watchdog timer 2021-09-02 09:09:00 +08:00
ld deep sleep: add deep sleep support for esp32s3 2021-10-20 11:36:20 +08:00
port cpu_start: rename function to add core prefix for more clarity 2021-10-20 15:16:25 +05:30
test ci: replacing old header with new SPDX header style 2021-10-20 11:36:23 +08:00
test_eh_frame_parser
CMakeLists.txt WDT: Add support for XTAL32K Watchdog timer 2021-09-02 09:09:00 +08:00
Kconfig deep sleep: fix some rtc fast memory definition errors in esp32s3 2021-10-19 21:47:27 +08:00
Makefile.projbuild
README.md
app.lf
component.mk esp_system: create ld template to abstract few common settings 2021-09-02 16:13:17 +08:00
crosscore_int.c
dbg_stubs.c gcov: add stub table size entry 2021-08-20 15:00:55 +08:00
eh_frame_parser.c
esp_err.c
esp_system.c
fpga_overrides.c
freertos_hooks.c
int_wdt.c gptimer: clean up hal and ll for driver-ng 2021-10-20 18:40:08 +08:00
linker.lf
panic.c esp_system: make the abort operation compatible with clang 2021-09-16 11:07:54 +02:00
sdkconfig.rename
stack_check.c
startup.c light sleep: add software workaround for esp32s3 gpio reset issue 2021-10-20 11:36:22 +08:00
system_time.c
task_wdt.c gptimer: clean up hal and ll for driver-ng 2021-10-20 18:40:08 +08:00
ubsan.c
xt_wdt.c WDT: Add support for XTAL32K Watchdog timer 2021-09-02 09:09:00 +08:00

README.md

System Notes

Timekeeping

The following are the timekeeping mechanisms available and their differences:

  1. System time (esp_system_get_time)

Time with the origin at g_startup_time. The implementation is not handled by esp_system, but it does provide a default implementation using RTC timer. Currently, esp_timer provides system time, since the hardware timers are under the control of that component. However, no matter the underlying timer, the system time provider should maintain the definition of having the origin point at g_startup_time.

  1. esp_timer time (esp_timer_get_time)

This is the time read from an underlying hardware timer, controlled through config. Origin is at the point where the underlying timer starts counting.

  1. newlib time (gettimeofday)

Timekeeping function in standard library. Can be set (settimeofday) or moved forward/backward (adjtime); with the possibility of the changes being made persistent through config. Currently implemented in terms of system time, as the point of origin is fixed. If persistence is enabled, RTC time is also used in conjuction with system time.

  1. RTC time (esp_rtc_get_time_us)

Time read from RTC timer.