USB Serial application
Fork of USBSerial_HelloWorld by
mbed-dev/targets/TARGET_STM/us_ticker_16b.c
- Committer:
- Zaitsev
- Date:
- 2017-12-16
- Revision:
- 11:b3f2a8bdac4d
- Parent:
- 10:41552d038a69
File content as of revision 11:b3f2a8bdac4d:
/* mbed Microcontroller Library * Copyright (c) 2006-2016 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. */ #include <stddef.h> #include "us_ticker_api.h" #include "PeripheralNames.h" #include "hal_tick.h" // A 16-bit timer is used #if TIM_MST_16BIT TIM_HandleTypeDef TimMasterHandle; volatile uint32_t SlaveCounter = 0; volatile uint32_t oc_int_part = 0; volatile uint16_t oc_rem_part = 0; volatile uint8_t tim_it_update; // TIM_IT_UPDATE event flag set in timer_irq_handler() volatile uint32_t tim_it_counter = 0; // Time stamp to be updated by timer_irq_handler() static int us_ticker_inited = 0; void set_compare(uint16_t count) { TimMasterHandle.Instance = TIM_MST; // Set new output compare value __HAL_TIM_SetCompare(&TimMasterHandle, TIM_CHANNEL_1, count); // Enable IT __HAL_TIM_ENABLE_IT(&TimMasterHandle, TIM_IT_CC1); } void us_ticker_init(void) { if (us_ticker_inited) return; us_ticker_inited = 1; TimMasterHandle.Instance = TIM_MST; HAL_InitTick(0); // The passed value is not used } uint32_t us_ticker_read() { uint32_t counter; TimMasterHandle.Instance = TIM_MST; if (!us_ticker_inited) us_ticker_init(); #if defined(TARGET_STM32L0) uint16_t cntH_old, cntH, cntL; do { // For some reason on L0xx series we need to read and clear the // overflow flag which give extra time to propelry handle possible // hiccup after ~60s if (__HAL_TIM_GET_FLAG(&TimMasterHandle, TIM_FLAG_CC1OF) == SET) { __HAL_TIM_CLEAR_FLAG(&TimMasterHandle, TIM_FLAG_CC1OF); } cntH_old = SlaveCounter; if (__HAL_TIM_GET_FLAG(&TimMasterHandle, TIM_FLAG_UPDATE) == SET) { cntH_old += 1; } cntL = TIM_MST->CNT; cntH = SlaveCounter; if (__HAL_TIM_GET_FLAG(&TimMasterHandle, TIM_FLAG_UPDATE) == SET) { cntH += 1; } } while(cntH_old != cntH); // Glue the upper and lower part together to get a 32 bit timer return (uint32_t)(cntH << 16 | cntL); #else tim_it_update = 0; // Clear TIM_IT_UPDATE event flag counter = TIM_MST->CNT + (uint32_t)(SlaveCounter << 16); // Calculate new time stamp if (tim_it_update == 1) { return tim_it_counter; // In case of TIM_IT_UPDATE return the time stamp that was calculated in timer_irq_handler() } else { return counter; // Otherwise return the time stamp calculated here } #endif } void us_ticker_set_interrupt(timestamp_t timestamp) { int delta = (int)((uint32_t)timestamp - us_ticker_read()); uint16_t cval = TIM_MST->CNT; if (delta <= 0) { // This event was in the past us_ticker_irq_handler(); } else { oc_int_part = (uint32_t)(delta >> 16); oc_rem_part = (uint16_t)(delta & 0xFFFF); if (oc_rem_part <= (0xFFFF - cval)) { set_compare(cval + oc_rem_part); oc_rem_part = 0; } else { set_compare(0xFFFF); oc_rem_part = oc_rem_part - (0xFFFF - cval); } } } void us_ticker_disable_interrupt(void) { TimMasterHandle.Instance = TIM_MST; __HAL_TIM_DISABLE_IT(&TimMasterHandle, TIM_IT_CC1); } void us_ticker_clear_interrupt(void) { TimMasterHandle.Instance = TIM_MST; if (__HAL_TIM_GET_FLAG(&TimMasterHandle, TIM_FLAG_CC1) == SET) { __HAL_TIM_CLEAR_FLAG(&TimMasterHandle, TIM_FLAG_CC1); } } #endif // TIM_MST_16BIT