/*!
    \file    readme.txt
    \brief   description of the communication_among_CANS demo
    
    \version 2025-07-31, V3.3.2, firmware for GD32F4xx
*/

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*/

  This demo is based on the GD32450I-EVAL-V1.1 board, it shows how to configure the 
CAN0 and CAN1 peripherals to send and receive CAN frames in normal mode. Because this 
board just has only one transceiver for CAN0, so you can test the function with the 
help of hyperterminal and CAN box. 

  If the other board has two transceivers for CAN0 and CAN1 respectively. The whole 
function can be test by connect the CAN0_H with the CAN1_H and the CAN0_L with the 
CAN1_L.

  When Tamper button is pressed, CAN0 sends a message to CAN box and print it.
when the hyperterminal correctly receive this message, the receive data will be 
show on the hyperterminal. 

  When the hyperterminal sends a message to CAN0. The CAN0 receives correctly 
this message,the receive data will be printed and LED4 toggles one time.

  User can select one from the preconfigured CAN baud rates from the private 
defines in main.c. These baudrates is correct only when the system clock frequency 
is 200M.

