circuitpython/ports/stm32/softtimer.h
Damien George a5d97f1db9 stm32: Add soft timer implementation, using SysTick at 1ms resolution.
This commit adds an implementation of a "software timer" with a 1ms
resolution, using SysTick.  It allows unlimited number of concurrent
timers (limited only by memory needed for each timer entry).  They can be
one-shot or periodic, and associated with a Python callback.

There is a very small overhead added to the SysTick IRQ, which could be
further optimised in the future, eg by patching SysTick_Handler code
dynamically.
2019-10-31 22:12:55 +11:00

51 lines
1.9 KiB
C

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2019 Damien P. George
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#ifndef MICROPY_INCLUDED_STM32_SOFTTIMER_H
#define MICROPY_INCLUDED_STM32_SOFTTIMER_H
#include "py/obj.h"
#define SOFT_TIMER_MODE_ONE_SHOT (1)
#define SOFT_TIMER_MODE_PERIODIC (2)
typedef struct _soft_timer_entry_t {
mp_obj_base_t base; // so struct can be used as an object and still be traced by GC
struct _soft_timer_entry_t *next;
uint32_t mode;
uint32_t expiry_ms;
uint32_t delta_ms; // for periodic mode
mp_obj_t callback;
} soft_timer_entry_t;
extern volatile uint32_t soft_timer_next;
void soft_timer_deinit(void);
void soft_timer_handler(void);
void soft_timer_insert(soft_timer_entry_t *entry);
void soft_timer_remove(soft_timer_entry_t *entry);
#endif // MICROPY_INCLUDED_STM32_SOFTTIMER_H