Diff: targets/TARGET_STM/us_ticker.c

Revision:

186:707f6e361f3e

Child:

187:0387e8f68319

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/targets/TARGET_STM/us_ticker.c	Fri Jun 22 16:45:37 2018 +0100
@@ -0,0 +1,80 @@
+/* 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"
+
+#if TIM_MST_16BIT
+#define TIMER_TICKER_BIT_WIDTH 16
+#else
+#define TIMER_TICKER_BIT_WIDTH 32
+#endif
+
+TIM_HandleTypeDef TimMasterHandle;
+
+const ticker_info_t* us_ticker_get_info()
+{
+    static const ticker_info_t info = {
+        1000000,
+        TIMER_TICKER_BIT_WIDTH
+    };
+    return &info;
+}
+
+void us_ticker_init(void)
+{
+    /* NOTE: assuming that HAL tick has already been initialized! */
+    __HAL_TIM_DISABLE_IT(&TimMasterHandle, TIM_IT_CC1);
+}
+
+uint32_t us_ticker_read()
+{
+    return TIM_MST->CNT;
+}
+
+void us_ticker_set_interrupt(timestamp_t timestamp)
+{
+    // NOTE: This function must be called with interrupts disabled to keep our
+    //       timer interrupt setup atomic
+    // Set new output compare value
+    __HAL_TIM_SET_COMPARE(&TimMasterHandle, TIM_CHANNEL_1, (uint32_t)timestamp);
+    // Ensure the compare event starts clear
+    __HAL_TIM_CLEAR_FLAG(&TimMasterHandle, TIM_FLAG_CC1);
+    // Enable IT
+    __HAL_TIM_ENABLE_IT(&TimMasterHandle, TIM_IT_CC1);
+}
+
+void us_ticker_fire_interrupt(void)
+{
+    __HAL_TIM_CLEAR_FLAG(&TimMasterHandle, TIM_FLAG_CC1);
+    LL_TIM_GenerateEvent_CC1(TimMasterHandle.Instance);
+    // Enable IT
+    __HAL_TIM_ENABLE_IT(&TimMasterHandle, TIM_IT_CC1);
+}
+
+/* NOTE: must be called with interrupts disabled! */
+void us_ticker_disable_interrupt(void)
+{
+    __HAL_TIM_DISABLE_IT(&TimMasterHandle, TIM_IT_CC1);
+}
+
+/* NOTE: must be called with interrupts disabled! */
+void us_ticker_clear_interrupt(void)
+{
+    __HAL_TIM_CLEAR_FLAG(&TimMasterHandle, TIM_FLAG_CC1);
+}
+