STM8S/A Standard Peripherals Firmware Library: Networking with CAN to control Leds

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  * @file    CAN/CAN_Networking/readme.txt
  * @author  MCD Application Team
  * @version V2.2.0
  * @date    30-September-2014
  * @brief   This file contains the main function for CAN networking example.
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  * Licensed under MCD-ST Liberty SW License Agreement V2, (the "License");
  * You may not use this file except in compliance with the License.
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Example description

This example provides a short description of how to use the CAN peripheral: CAN peripheral is configured to send and receive CAN frames. The sent frames are used to control Leds. An LCD is used to give information about :

• CAN sender (sender of the frame)
• CAN receiver (receiver of the frame)
• Controlled Led (set ON)

The CAN serial communication link is a bus to which a number of units may be connected. This number has no theoretical limit. Practically the total number of units will be limited by delay times and/or electrical loads on the bus line.

Note:

This example is tested with a bus of 3 units. The same program example is loaded in all units to send and receive frames.

CAN is configured as follow:

• Bit Rate = 1 Mbit/s
• CAN Clock = Internal (HSI)
• ID Filter = All identifiers are allowed
• RTR = Data
• DLC = 1 byte

Directory contents

• CAN\CAN_Networking\main.c Main file containing the "main" function
• CAN\CAN_Networking\main.h Main file declaration
• CAN\CAN_Networking\stm8s_conf.h Library Configuration file
• CAN\CAN_Networking\stm8s_it.c Interrupt routines source
• CAN\CAN_Networking\stm8s_it.h Interrupt routines declaration

Hardware environment

• This example runs only on STM8S208 and STM8A52Ax devices.

• This example has been tested with STMicroelectronics STM8/128-EVAL evaluation board and can be easily tailored to any other development board.

• STM8/128-EVAL Set-up
  • Key push button
  • LD1..LD4
  • Mono LCD

• If another board is used, consider the folloing hardware connections :
  • PH3 -> LED1 -> resistor -> ground
  • PH2 -> LED2 -> resistor -> ground
  • PH1 -> LED3 -> resistor -> ground
  • PH0 -> LED4 -> resistor -> ground
  • PC0 -> Key Button -> ground + pull-up on 5V
  • PG1 (CAN Rx) and PG0 (CAN Tx) connected to a DB9 connector using a CAN Bus transceiver (eg. L9616).

• Connect a female/female CAN cable between at least 2 EVAL CAN connectors (CN8 on STM8/128-EVAL board)
  • Connector 1 DB9_PIN2 to Connector 2 DB9_PIN2 (CAN_L)
  • Connector 1 DB9_PIN5 to Connector 2 DB9_PIN5 ( GND )
  • Connector 1 DB9_PIN7 to Connector 2 DB9_PIN7 (CAN_H)

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
• Open your preferred toolchain
• Add the required file:
  • stm8s_eval_lcd.c (under Utilities)
• Rebuild all files and load your image into target memory
• Run the example
• In the first time the LCD shows the message "STM8S CAN Press Key".
• (1) By Pressing on Key Button : CAN send a Frame to command LED1 (LD1 ON) on the N eval-boards connected to the bus, all other Leds are OFF. The sender LCD shows "STM8S CAN Sender LD1 ON". The N-1 receivers LCD shows "STM8S CAN Receiver LD1 ON".
• Press on Key Button again to send CAN Frame to command LD2 ON on the N eval-boards, all other Leds are OFF. The sender LCD shows "STM8S CAN Sender LD2 ON". The N-1 receivers LCD shows "STM8S CAN Receiver LD2 ON".
• Press on Key Button again to send CAN Frame to command LD3 ON on the N eval-boards, all other Leds are OFF. The sender LCD shows "STM8S CAN Sender LD3 ON". The N-1 receivers LCD shows "STM8S CAN Receiver LD3 ON".
• Press on Key Button again to send CAN Frame to command LD4 ON on the N eval-boards, all other Leds are OFF. The sender LCD shows "STM8S CAN Sender LD4 ON". The N-1 receivers LCD shows "STM8S CAN Receiver LD4 ON".
• Press on Key Button again to go to step (1)

  Note:

  Any unit in the CAN bus may play the role of sender (by pressing on the key) or receiver.

• High-Density STM8A devices are the STM8AF52xx STM8AF6269/8x/Ax, STM8AF51xx, and STM8AF6169/7x/8x/9x/Ax microcontrollers where the Flash memory density ranges between 32 to 128 Kbytes
• Medium-Density STM8A devices are the STM8AF622x/4x, STM8AF6266/68, STM8AF612x/4x, and STM8AF6166/68 microcontrollers where the Flash memory density ranges between 8 to 32 Kbytes
• High-Density STM8S devices are the STM8S207xx, STM8S007 and STM8S208xx microcontrollers where the Flash memory density ranges between 32 to 128 Kbytes.
• Medium-Density STM8S devices are the STM8S105x and STM8S005 microcontrollers where the Flash memory density ranges between 16 to 32-Kbytes.
• Low-Density STM8S devices are the STM8S103xx, STM8S003 and STM8S903xx microcontrollers where the Flash density is 8 Kbytes.

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