mbed-os/targets/TARGET_STM/hal_tick_overrides.c

83 lines
2.1 KiB
C

/* mbed Microcontroller Library
* Copyright (c) 2006-2018 ARM Limited
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#if DEVICE_USTICKER
#include "hal/us_ticker_api.h"
#include "us_ticker_data.h"
// This variable is set to 1 at the of mbed_sdk_init function.
// The ticker_read_us function must not be called until the mbed_sdk_init is terminated.
extern int mbed_sdk_inited;
// Defined in us_ticker.c
void init_16bit_timer(void);
void init_32bit_timer(void);
#if TIM_MST_BIT_WIDTH == 16
// Variables also reset in us_ticker_init()
uint32_t prev_time = 0;
uint32_t elapsed_time = 0;
#endif
// Overwrite default HAL functions defined as "weak"
HAL_StatusTypeDef HAL_InitTick(uint32_t TickPriority)
{
#if TIM_MST_BIT_WIDTH == 16
init_16bit_timer();
#else
init_32bit_timer();
#endif
return HAL_OK;
}
uint32_t HAL_GetTick()
{
#if TIM_MST_BIT_WIDTH == 16
uint32_t new_time;
if (mbed_sdk_inited) {
// Apply the latest time recorded just before the sdk is inited
new_time = ticker_read_us(get_us_ticker_data()) + prev_time;
prev_time = 0; // Use this time only once
return (new_time / 1000);
} else {
new_time = us_ticker_read();
elapsed_time += (new_time - prev_time) & 0xFFFF; // Only use the lower 16 bits
prev_time = new_time;
return (elapsed_time / 1000);
}
#else // 32-bit timer
if (mbed_sdk_inited) {
return (ticker_read_us(get_us_ticker_data()) / 1000);
} else {
return (us_ticker_read() / 1000);
}
#endif
}
void HAL_SuspendTick(void)
{
// Do nothing
}
void HAL_ResumeTick(void)
{
// Do nothing
}
#endif /* DEVICE_USTICKER */