NVIC_DMA_WFIMode

  ******************** (C) COPYRIGHT 2010 STMicroelectronics *******************
  * @file    NVIC/DMA_WFIMode/readme.txt 
  * @author  MCD Application Team
  * @version V3.4.0
  * @date    10/15/2010
  * @brief   Description of the NVIC DMA in WFI mode 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.
  ******************************************************************************
   
Example Description

This example shows how to enters the system to WFI mode with DMA transfer enabled and wake-up from this mode by the DMA End of Transfer interrupt.

In the associated software, the system clock is set to 72 MHz (24MHz on Value line), the DMA1 Channely is configured to transfer 10 data from the EVAL COM1 USART data register to a predefined buffer, DST_Buffer, and to generate an interrupt at the end of the transfer. The EVAL COM1 USART receives data from Hyperterminal. A LED1 is toggled with a frequency depending on the system clock, this is used to indicate whether the MCU is in WFI or RUN mode.

A falling edge on the selected EXTI Line will put the core in the WFI mode, causing the led pin to stop toggling. To wake-up from WFI mode you have to send the sequence (0, 1, 2, 3, 4, 5, 6, 7, 8, 9) from the Hyperterminal to the EVAL COM1 USART. These bytes will be transferred by the DMA from the EVAL COM1 receive data register to the predefined buffer, then generates an interrupt which exits the system from WFI mode. The LED1 restarts toggling and a LED2 will toggle if the buffer is correctly received else a LED3 is toggled.

Directory contents
Hardware and Software environment
How to use it ?

In order to make the program work, you must do the following :

Tip: You can tailor the provided project template to run this example, for more details please refer to "stm32f10x_stdperiph_lib_um.chm" user manual; select "Peripheral Examples" then follow the instructions provided in "How to proceed" section.

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.

© COPYRIGHT 2010 STMicroelectronics

STM32F10x Standard Peripherals Library: Footer

 

 

 

      For complete documentation on STM32(CORTEX M3) 32-bit Microcontrollers platform visit  www.st.com/STM32