GigaDevice Semiconductor GD32450Z-EVAL - EXTI Key Interrupt Mode Demo; USART Printf Example Demo

User Guide
GD32450Z-EVAL
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5.3. EXTI_Key_Interrupt_mode
5.3.1. 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
GD32450Z-EVAL-V1.1 board has four keys and three LEDs. The four keys are Reset key,
Tamper key, Wakeup key and User key. The LED1, LED2 and LED3 are controlled by
GPIO.
This demo will show how to use the EXTI interrupt line to control the LED2.When press
down the Tamper Key, it will produce an interrupt. In the interrupt service function, the
demo will toggle LED1.
5.3.2. DEMO running result
Download the program <03_EXTI_Key_Interrupt_mode> to the EVAL board, press down
the Tamper Key, LED1 will be turned on. Press down the Tamper Key again, LED1 will
be turned off.
5.4. USART_Printf
5.4.1. DEMO purpose
This demo includes the following functions of GD32 MCU:
 Learn to use GPIO control the LED
 Learn to retarget the C library printf function to the USART
5.4.2. DEMO running result
Download the program < 04_USART_Printf > to the EVAL board, connect serial cable to
COM0 and jump JP13 to USART. This implementation outputs “USART printf example:
please press the Tamper key” on the HyperTerminal using COM0. Press the Tamper key,
the LED1 will be turned on and serial port will output “USART printf example”.
The output information via the serial port is as following.