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diff --git a/tmp/STM32F10x_StdPeriph_Lib_V3.5.0/Project/STM32F10x_StdPeriph_Examples/RTC/LSI_Calib/readme.txt b/tmp/STM32F10x_StdPeriph_Lib_V3.5.0/Project/STM32F10x_StdPeriph_Examples/RTC/LSI_Calib/readme.txt new file mode 100644 index 0000000..f465c39 --- /dev/null +++ b/tmp/STM32F10x_StdPeriph_Lib_V3.5.0/Project/STM32F10x_StdPeriph_Examples/RTC/LSI_Calib/readme.txt @@ -0,0 +1,111 @@ + +/** + @page RTC_LSI_Calib RTC LSI_Calib example + + @verbatim + ******************** (C) COPYRIGHT 2011 STMicroelectronics ******************* + * @file RTC/LSI_Calib/readme.txt + * @author MCD Application Team + * @version V3.5.0 + * @date 08-April-2011 + * @brief Description of the RTC LSI_Calib example. + ****************************************************************************** + * THE PRESENT FIRMWARE WHICH IS FOR GUIDANCE ONLY AIMS AT PROVIDING CUSTOMERS + * WITH CODING INFORMATION REGARDING THEIR PRODUCTS IN ORDER FOR THEM TO SAVE + * TIME. AS A RESULT, STMICROELECTRONICS SHALL NOT BE HELD LIABLE FOR ANY + * DIRECT, INDIRECT OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING + * FROM THE CONTENT OF SUCH FIRMWARE AND/OR THE USE MADE BY CUSTOMERS OF THE + * CODING INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS. + ****************************************************************************** + @endverbatim + +@par Example Description + +This example demonstrates and explains how to use the LSI clock source auto +calibration to get a precise RTC clock. +As an application example, it demonstrates how to configure the TIM5 timer +internally connected to LSI clock output, in order to adjust the RTC prescaler. + +The Low Speed External (LSI) clock is used as RTC clock source. +After reset, the RTC prescaler is set with the default value (40000). +The inaccuracy of the LSI clock causes the RTC Second signal to be inaccurate. This +signal is output on the Tamper pin (PC.13) and can be measured by on oscilloscope +or a frequencymeter. + +The program waits until Key Push button is pressed to begin the auto calibration procedure: + - Configure the TIM5 to remap internally the TIM5 Channel 4 Input Capture to the + LSI clock output. + - Enable the TIM5 Input Capture interrupt: after one cycle of LSI clock, the + period value is stored in a variable and compared to the HCLK clock to get + its real value. + - The RTC prescaler is adjusted with this LSI frequency value so that the RTC + Second value become more accurate. + - When calibration is done a led connected to PF.07 is turned ON to indicate the + end of this operation. At this moment, you can monitor the Second signal on + an oscilloscope to measure its accuracy again. + +The RTC Second signal can be monitored either on Tamper pin or on LED1 which is +toggled into the RTC Second interrupt service routine. + + +@par Directory contents + + - RTC/LSI_Calib/stm32f10x_conf.h Library Configuration file + - RTC/LSI_Calib/stm32f10x_it.c Interrupt handlers + - RTC/LSI_Calib/stm32f10x_it.h Header for stm32f10x_it.c + - RTC/LSI_Calib/main.h Main header file + - RTC/LSI_Calib/main.c Main program + - RTC/LSI_Calib/system_stm32f10x.c STM32F10x system source file + +@par Hardware and Software environment + + - This example runs on STM32F10x Connectivity line, High-Density Value line, + High-Density and XL-Density Devices. + + - This example has been tested with STMicroelectronics STM32100E-EVAL (High-Density + Value line), STM3210E-EVAL (High-Density and XL-Density) and STM3210C-EVAL + (Connectivity Line) evaluation boards and can be easily tailored to any other + supported device and development board. + To select the STMicroelectronics evaluation board used to run the example, + uncomment the corresponding line in stm32_eval.h file (under Utilities\STM32_EVAL) + + - STM32100E-EVAL Set-up + - Use LD1 and LD2 leds connected respectively to PF.06 and PF.07 pins + - Use the Key push button connected to PG.08 pin + + - STM3210C-EVAL Set-up + - Use LD1 and LD2 leds connected respectively to PD.07 and PD.13 pins + - Use the Key push-button connected to PB.09 pin + + - STM3210E-EVAL Set-up + - Use LD1 and LD2 leds connected respectively to PF.06 and PF.07 pins + - Use the Key push button connected to PG.08 pin + +@par How to use it ? + +In order to make the program work, you must do the following : + - Copy all source files from this example folder to the template folder under + Project\STM32F10x_StdPeriph_Template + - Open your preferred toolchain + - Rebuild all files and load your image into target memory + - Run the example + +@note + - Low-density Value line devices are STM32F100xx microcontrollers where the + Flash memory density ranges between 16 and 32 Kbytes. + - Low-density devices are STM32F101xx, STM32F102xx and STM32F103xx + microcontrollers where the Flash memory density ranges between 16 and 32 Kbytes. + - Medium-density Value line devices are STM32F100xx microcontrollers where + the Flash memory density ranges between 64 and 128 Kbytes. + - Medium-density devices are STM32F101xx, STM32F102xx and STM32F103xx + microcontrollers where the Flash memory density ranges between 64 and 128 Kbytes. + - High-density Value line devices are STM32F100xx microcontrollers where + the Flash memory density ranges between 256 and 512 Kbytes. + - High-density devices are STM32F101xx and STM32F103xx microcontrollers where + the Flash memory density ranges between 256 and 512 Kbytes. + - XL-density devices are STM32F101xx and STM32F103xx microcontrollers where + the Flash memory density ranges between 512 and 1024 Kbytes. + - Connectivity line devices are STM32F105xx and STM32F107xx microcontrollers. + + * <h3><center>© COPYRIGHT 2011 STMicroelectronics</center></h3> + */ |