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+/**
+  @page TIM_InputCapture Input Capture example
+  
+  @verbatim
+  ******************************************************************************
+  * @file    TIM/TIM_InputCapture/readme.txt 
+  * @author  MCD Application Team
+  * @brief   Description of the TIM_InputCapture example.
+  ******************************************************************************
+  *
+  * Copyright (c) 2019 STMicroelectronics. All rights reserved.
+  *
+  * This software component is licensed by ST under BSD 3-Clause license,
+  * the "License"; You may not use this file except in compliance with the
+  * License. You may obtain a copy of the License at:
+  *                       opensource.org/licenses/BSD-3-Clause
+  *
+  ******************************************************************************
+  @endverbatim
+
+@par Example Description
+
+How to use the TIM peripheral to measure an external signal frequency.
+ 
+  At the beginning of the main program the HAL_Init() function is called to reset 
+  all the peripherals, initialize the Flash interface and the systick.
+  The SystemClock_Config() function is used to configure the system clock for STM32WB55RGVx Devices :
+  The CPU at 64 MHz 
+
+  The TIM2CLK frequency is set to SystemCoreClock  (Hz), the Prescaler is 0,
+  so the TIM2 counter clock is SystemCoreClock  (Hz).
+
+  SystemCoreClock is set to 64 MHz for STM32WB55RGVx Devices.
+
+  TIM2 is configured in Input Capture Mode: the external signal is connected to 
+  TIM2 Channel2 used as input pin.
+  To measure the frequency we use the TIM2 CC interrupt request, so in the 
+  TIM2 CC IRQHandler routine, the frequency of the external signal is computed.
+
+  The "uwFrequency" variable contains the external signal frequency:
+  uwFrequency = TIM2 counter clock / uwDiffCapture (Hz),
+  where "uwDiffCapture" is the difference between two consecutive TIM2 captures.
+
+  The minimum frequency value to measure is TIM2 counter clock / CCR MAX
+                                              = (SystemCoreClock) / 65535
+
+  Due to TIM2 CC IRQHandler processing time (around 3.12us), the maximum
+  frequency value to measure is around 320kHz.
+
+@note Care must be taken when using HAL_Delay(), this function provides accurate delay (in milliseconds)
+      based on variable incremented in SysTick ISR. This implies that if HAL_Delay() is called from
+      a peripheral ISR process, then the SysTick interrupt must have higher priority (numerically lower)
+      than the peripheral interrupt. Otherwise the caller ISR process will be blocked.
+      To change the SysTick interrupt priority you have to use HAL_NVIC_SetPriority() function.
+
+@note This example needs to ensure that the SysTick time base is always set to 1 millisecond
+      to have correct HAL operation.
+
+
+@par Keywords
+
+Timer, DMA, Frequency, Input, Capture, External Signal, Measurement
+
+@par Directory contents
+
+  - TIM/TIM_InputCapture/Inc/stm32wbxx_hal_conf.h    HAL configuration file
+  - TIM/TIM_InputCapture/Inc/stm32wbxx_it.h          Interrupt handlers header file
+  - TIM/TIM_InputCapture/Inc/main.h                  Header for main.c module  
+  - TIM/TIM_InputCapture/Src/stm32wbxx_it.c          Interrupt handlers
+  - TIM/TIM_InputCapture/Src/main.c                  Main program
+  - TIM/TIM_InputCapture/Src/stm32wbxx_hal_msp.c     HAL MSP file
+  - TIM/TIM_InputCapture/Src/system_stm32wbxx.c      STM32WBxx system source file
+
+
+@par Hardware and Software environment
+
+  - This example runs on STM32WB55xx devices.
+  - In this example, the clock is set to 64 MHz.
+    
+  - This example has been tested with STMicroelectronics P-NUCLEO-WB55
+    board and can be easily tailored to any other supported device 
+    and development board.      
+
+  - P-NUCLEO-WB55 Set-up
+    - Connect the external signal to measure to the TIM2 CH2 pin (PA.01 (pin 32 in CN7 connector)).
+
+@par How to use it ? 
+
+In order to make the program work, you must do the following :
+ - Open your preferred toolchain 
+ - Rebuild all files and load your image into target memory
+ - Run the example
+
+ * <h3><center>&copy; COPYRIGHT STMicroelectronics</center></h3>
+ */