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/**
@page UART_HyperTerminal_DMA UART Hyperterminal DMA Example
@verbatim
******************** (C) COPYRIGHT 2017 STMicroelectronics *******************
* @file UART/UART_HyperTerminal_DMA/readme.txt
* @author MCD Application Team
* @brief Description of the UART Hyperterminal example.
******************************************************************************
*
* 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
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* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
******************************************************************************
@endverbatim
@par Example Description
This example describes an UART transmission (transmit/receive) in DMA mode
between a board and an HyperTerminal PC application.
Board: STM32469I-EVAL
Tx Pin: PA.09
Rx Pin: PA.10
_________________________
| ______________| _______________
| |USART | | HyperTerminal |
| | | | |
| | TX |______________________|RX |
| | | | |
| | | RS232 Cable | |
| | | | |
| | RX |______________________|TX |
| | | | |
| |______________| |_______________|
| |
| |
| |
| |
|_STM32_Board_____________|
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.
Then the SystemClock_Config() function is used to configure the system
clock (SYSCLK) to run at 180 MHz for STM32F4xx Devices.
The UART peripheral configuration is ensured by the HAL_UART_Init() function.
This later is calling the HAL_UART_MspInit()function which core is implementing
the configuration of the needed UART resources according to the used hardware (CLOCK,
GPIO, DMA and NVIC). You may update this function to change UART configuration.
The UART/Hyperterminal communication is then initiated.
The HAL_UART_Receive_DMA() and the HAL_UART_Transmit_DMA() functions allow respectively
the reception of Data from Hyperterminal and the transmission of a predefined data
buffer.
The Asynchronous communication aspect of the UART is clearly highlighted as the
data buffers transmission/reception to/from Hyperterminal are done simultaneously.
For this example the TxBuffer is predefined and the RxBuffer size is limited to
10 data by the mean of the RXBUFFERSIZE define in the main.c file.
In a first step the received data will be stored in the RxBuffer buffer and the
TxBuffer buffer content will be displayed in the Hyperterminal interface.
In a second step the received data in the RxBuffer buffer will be sent back to
Hyperterminal and displayed.
The end of this two steps are monitored through the HAL_UART_GetState() function
result.
STM32 board's LEDs can be used to monitor the transfer status:
- LED1 is ON when the transmission process is complete.
- LED2 is ON when the reception process is complete.
- LED3 is ON when there is an error in transmission/reception process.
The UART is configured as follows:
- BaudRate = 9600 baud
- Word Length = 8 Bits (7 data bit + 1 parity bit)
- One Stop Bit
- Odd parity
- Hardware flow control disabled (RTS and CTS signals)
- Reception and transmission are enabled in the time
@note USARTx/UARTx instance used and associated resources can be updated in "main.h"
file depending hardware configuration used.
@note When the parity is enabled, the computed parity is inserted at the MSB
position of the transmitted data.
@note When the UART parity is enabled (PCE = 1) the data received contain the parity bit.
@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 The application needs to ensure that the SysTick time base is always set to 1 millisecond
to have correct HAL operation.
@note The connection of the LCD reset pin to a dedicated GPIO PK7 instead of the STM32F469 NRST pin may cause residual display on LCD with applications/examples that do not require display.
The LCD clear can be ensured by hardware through the board's power off/power on or by software calling the BSP_LCD_Reset() function.
@par Keywords
Connectivity, UART, Printf, Baud rate, RS-232, HyperTerminal, full-duplex, HyperTerminal, DMA,
Transmission, Reception, Asynchronous
@par Directory contents
- UART/UART_HyperTerminal_DMA/Inc/stm32f4xx_hal_conf.h HAL configuration file
- UART/UART_HyperTerminal_DMA/Inc/stm32f4xx_it.h DMA interrupt handlers header file
- UART/UART_HyperTerminal_DMA/Inc/main.h Header for main.c module
- UART/UART_HyperTerminal_DMA/Src/stm32f4xx_it.c DMA interrupt handlers
- UART/UART_HyperTerminal_DMA/Src/main.c Main program
- UART/UART_HyperTerminal_DMA/Src/stm32f4xx_hal_msp.c HAL MSP module
- UART/UART_HyperTerminal_DMA/Src/system_stm32f4xx.c STM32F4xx system source file
@par Hardware and Software environment
- This example runs on STM32F469xx/STM32F479xx devices.
- This example has been tested and validated with STMicroelectronics STM32469I-EVAL RevC board and can be
easily tailored to any other supported device and development board.
- TARGET_STM32469I_EVAL Set-up
- Connect a null-modem female/female RS232 cable between the DB9 connector CN7 (USART1)
and PC serial port on which you want to display data on the HyperTerminal.
@note Make sure that :
- jumper JP8 is on RS232_RX position (1-2) and
- jumper JP15 is on USART1_RX position 1-2)and
- jumper JP19 is on USART1_TX position (1-2).
- Hyperterminal configuration:
- Word Length = 7 Bits
- One Stop Bit
- Odd parity
- BaudRate = 9600 baud
- flow control: None
@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>© COPYRIGHT STMicroelectronics</center></h3>
*/