/**
@page CEC CEC_DataExchange example
@verbatim
******************** (C) COPYRIGHT 2016 STMicroelectronics *******************
* @file CEC/CEC_DataExchange/readme.txt
* @author MCD Application Team
* @brief Description of the CEC Data Exchangeexample.
******************************************************************************
*
* 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
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
******************************************************************************
@endverbatim
@par Example Description
This example shows how to configure and use the CEC peripheral to receive and
transmit messages.
- Hardware Description
To use this example, two STM32072B-EVAL RevB boards (called Device_1 and
Device_2) are loaded with the same software then connected through CEC lines
(PB8 or HDMI connectors) and GND.
/|\ In the firmware file main.h, uncomment the dedicated line to use
/_!_\ the CEC peripheral as STM32 device_1 or STM32 device_2.
@verbatim
*------------------------------------------------------------------------------*
| STM32072B_EVAL STM32072B_EVAL |
| Device Address :0x01 Device Address :0x03 |
| ____________________ ____________________ |
| | | | | |
| | | | | |
| | __________ | | __________ | |
| | | CEC |____|____CECLine______|____| CEC | | |
| | | Device_1 | | | | Device_2 | | |
| | |__________| | | |__________| | |
| | | | | |
| | O LD1 | | O LD1 | |
| | O LD2 Joystick | | O LD2 Joystick | |
| | O LD3 _ | | O LD3 _ | |
| | O LD4 |_| | | O LD4 |_| | |
| | | | | |
| | GND O--|-----------------|--O GND | |
| |____________________| |____________________| |
| |
| |
*------------------------------------------------------------------------------**
@endverbatim
- Software Description
The test unrolls as follows.
On TX side, four possible messages can be transmitted and are indicated as
below on the transmitting board:
- when Tamper push-button is pressed, LED1 toggles
- when Joystick Sel push-button is pressed, LED2 toggles
- when Joystick UP push-button is pressed, LED3 toggles
- when Joystick DOWN push-button is pressed, LED4 toggles
Accordingly, the following happens on the RX side in case of successful
reception:
- when Tamper push-button is pressed on TX side,
* all RX side LEDs are turned off
- when Joystick Sel push-button is pressed on TX side, on RX side
* LED1 and LED2 are turned on
* LED3 and LED4 are turned off
- when Joystick UP push-button is pressed on TX side,
* all RX side LEDs are turned on
- when Joystick DOWN push-button is pressed on TX side, on RX side
* LED1 and LED2 are turned off
* LED3 and LED4 are turned on
In case of unsuccessful reception, LED3 is turned on.
Practically, 2 EXTI lines (EXTI0_1 and EXTI4_15) are configured to
generate an interrupt on each falling or rising edge.
A specific message is then transmitted by the CEC IP
and a LED connected to a specific GPIO pin is toggled.
- EXTI0_1 is mapped to PA.00
- EXTI4_15 is mapped to PC.13, PF.09 and PF.10
Then, on TX side,
- when rising edge is detected on EXTI0_1, LED2 toggles
- when falling edge is detected on EXTI4_15 and EXTI line interrupt is detected
on PC.13, LED1 toggles
- when falling edge is detected on EXTI4_15 and EXTI line interrupt is detected
on PF.09, LED3 toggles
- when falling edge is detected on EXTI4_15 and EXTI line interrupt is detected
on PF.10, LED4 toggles
In this example, HCLK is configured at 48 MHz.
@par Directory contents
- CEC/CEC_DataExchange/Inc/stm32f0xx_hal_conf.h HAL configuration file
- CEC/CEC_DataExchange/Inc/stm32f0xx_it.h Interrupt handlers header file
- CEC/CEC_DataExchange/Inc/main.h Header for main.c module
- CEC/CEC_DataExchange/Src/stm32f0xx_it.c Interrupt handlers
- CEC/CEC_DataExchange/Src/system_stm32f0xx.c STM32F0xx system source file
- CEC/CEC_DataExchange/Src/main.c Main program
- CEC/CEC_DataExchange/Src/stm32f0xx_hal_msp.c IP hardware resources initialization
@par Hardware and Software environment
- This example runs on STM32F072VB Devices.
- This example has been tested with STM32072B-EVAL RevB board and can be
easily tailored to any other supported device and development board.
@par How to use it ?
In order to make the program work, you must do the following :
- Open your preferred toolchain
- in main.h, uncomment DEVICE_1 for first board, uncomment DEVICE_2 for second board
- Rebuild all files and load your image into target memory
- With a wire, connect HDMI_CEC_LINE_GPIO_PORT-HDMI_CEC_LINE_PIN between the 2 boards
- Connect the ground of the 2 boards
- Run the example
* <h3><center>© COPYRIGHT STMicroelectronics</center></h3>
*/
