circuitpython/supervisor/shared/tick.h
2024-05-19 20:40:44 -04:00

45 lines
1.4 KiB
C

// This file is part of the CircuitPython project: https://circuitpython.org
//
// SPDX-FileCopyrightText: Copyright (c) 2019 Jeff Epler for Adafruit Industries
//
// SPDX-License-Identifier: MIT
#pragma once
#include <stdint.h>
#include <stdbool.h>
/** @brief To be called once every ms
*
* The port must call supervisor_tick once per millisecond to perform regular tasks.
* This is called from the SysTick interrupt or similar, and is safe to call in an
* interrupt context.
*/
extern void supervisor_tick(void);
/** @brief Get the lower 32 bits of the time in milliseconds
*
* This can be more efficient than supervisor_ticks_ms64, for sites where a wraparound
* of ~49.5 days is not harmful.
*/
extern uint32_t supervisor_ticks_ms32(void);
/** @brief Get the full time in milliseconds
*
* Because common ARM mcus cannot atomically work with 64-bit quantities, this
* function must briefly disable interrupts in order to return the value. If
* only relative durations of less than about ~49.5 days need to be considered,
* then it may be possible to use supervisor_ticks_ms32() instead.
*/
extern uint64_t supervisor_ticks_ms64(void);
extern void supervisor_enable_tick(void);
extern void supervisor_disable_tick(void);
/**
* @brief Return true if tick-based background tasks ran within the last 1s
*
* Note that when ticks are not enabled, this function can return false; this is
* intended.
*/
extern bool supervisor_background_ticks_ok(void);