/*!
    \file    readme.txt
    \brief   description of Comparator_Obtain_Brightness demo
    
    \version 2025-08-21, V2.5.0, demo for GD32L23x
*/

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*/

  This demo is based on the GD32L233R-EVAL-V1.1 board, it shows how to 
configure the comparator trigger interrupt using an external interrupt line.

  CMP0 is configured as following:
  - Inverting input is internally connected to VREFINT = 1.2V.
  - Non Inverting input is connected to VR(PA1).
  - Output is internally connected to EXTI line 21
  EXTI is configured as following:
  - Enable the exti line 21 interrupt.

  In this demo, connect VR1 to PA1, EXTI line 21 is configured to generate an 
interrupt on rising edge of the output signal. 
  After system start-up, if the Non Inverting input is bigger than 1.2V, LED2 is on,
otherwise, LED2 is off. 
