User Guide
GD32L233C-START
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5.5.
TIMER_Key_EXTI
5.5.1.
DEMO purpose
This demo includes the following functions of GD32 MCU:
Learn to use GPIO control the LED and the KEY
Learn to use EXTI to generate external interrupt
Learn to use TIMER to generate PWM
GD32L233C-START board has two keys and four LEDs. The two keys are Reset key and
Wakeup key. The LED1, LED2, LED3 and LED4 are controlled by GPIO.
This demo will show how to use the TIMER PWM to trigger EXTI interrupt to toggle the state
of LED2 and EXTI interrupt line to control the LED1. When press down the Wakeup Key, it
will produce an interrupt. In the interrupt service function, the demo will toggle LED1.
5.5.2.
DEMO running result
Download the program < 05_TIMER_Key_EXTI > to the START board, all the LED1 and
LED2 are flashed once for test, press down the Wakeup Key, LED1 will be turned on. Press
down the Wakeup Key again, LED1 will be turned off. Connect PA6 (TIMER2_CH0) and PA4
with DuPont line. The LED2 will be toggled every 500ms.
5.6.
USBD_CDC_ACM
5.6.1.
DEMO Purpose
This demo includes the following functions of GD32 MCU:
Learn how to use the USBD peripheral
Learn how to implement USB CDC device
GD32L233C-START board has one USBD interface. In this demo, the GD32L233C-START
board is enumerated as an USB virtual COM port, which was shown in device manager of
