mbed library sources. Supersedes mbed-src.
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Diff: targets/hal/TARGET_STM/TARGET_STM32L0/us_ticker.c
- Revision:
- 144:ef7eb2e8f9f7
- Parent:
- 136:5728e9819171
diff -r 423e1876dc07 -r ef7eb2e8f9f7 targets/hal/TARGET_STM/TARGET_STM32L0/us_ticker.c --- a/targets/hal/TARGET_STM/TARGET_STM32L0/us_ticker.c Tue Aug 02 14:07:36 2016 +0000 +++ b/targets/hal/TARGET_STM/TARGET_STM32L0/us_ticker.c Fri Sep 02 15:07:44 2016 +0100 @@ -1,130 +1,121 @@ -/* mbed Microcontroller Library - * Copyright (c) 2015, STMicroelectronics - * All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions are met: - * - * 1. Redistributions of source code must retain the above copyright notice, - * this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright notice, - * this list of conditions and the following disclaimer in the documentation - * and/or other materials provided with the distribution. - * 3. Neither the name of STMicroelectronics nor the names of its contributors - * may be used to endorse or promote products derived from this software - * without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" - * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE - * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE - * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL - * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR - * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER - * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, - * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE - * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. - */ -#include <stddef.h> -#include <stdbool.h> -#include "us_ticker_api.h" -#include "PeripheralNames.h" - -// Timer selection -#define TIM_MST TIM21 - -static TIM_HandleTypeDef TimMasterHandle; -static int us_ticker_inited = 0; -static bool us_ticker_stabilized = false; - -volatile uint16_t SlaveCounter = 0; -volatile uint32_t oc_int_part = 0; -volatile uint16_t oc_rem_part = 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; - - HAL_InitTick(0); // The passed value is not used -} - -uint32_t us_ticker_read() -{ - volatile uint16_t cntH_old, cntH, cntL; - - if (!us_ticker_inited) us_ticker_init(); - - // There's a situation where the first tick still may overflow and to avoid - // it we need to check if our ticker has stabilized and due to that we need - // to return only the lower part of your 32 bit software timer. - if (us_ticker_stabilized) { - 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); - } else { - us_ticker_stabilized = true; - return (uint32_t) TIM_MST->CNT; - } - - // Glue the upper and lower part together to get a 32 bit timer - return (uint32_t)(cntH << 16 | cntL); -} - -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); - } -} +/* mbed Microcontroller Library + * Copyright (c) 2015, STMicroelectronics + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * 3. Neither the name of STMicroelectronics nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE + * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR + * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER + * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, + * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#include <stddef.h> +#include <stdbool.h> +#include "us_ticker_api.h" +#include "PeripheralNames.h" + +// Timer selection +#define TIM_MST TIM21 + +static TIM_HandleTypeDef TimMasterHandle; +static int us_ticker_inited = 0; + +volatile uint16_t SlaveCounter = 0; +volatile uint32_t oc_int_part = 0; +volatile uint16_t oc_rem_part = 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; + + HAL_InitTick(0); // The passed value is not used +} + +uint32_t us_ticker_read() +{ + volatile uint16_t cntH_old, cntH, cntL; + + if (!us_ticker_inited) us_ticker_init(); + + 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); +} + +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); + } +}